From Paterva Wiki
Although a lot of effort has been put into making Maltego stable and usable there are always things that can be improved. Here follows a list of things that we just did not get to before release date. These problems will be fixed in upcoming version of the tool.
If this is open source, where can I get the source?
Open source intelligence, not be confused with open source software. Let's Google it and read the very first hit: 
Open source intelligence (OSINT) is form of intelligence collection management that involves finding, selecting, and acquiring information from publicly available sources and analyzing it to produce actionable intelligence. In the intelligence community (IC), the term "open" refers to overt, publicly available sources (as opposed to covert or classified sources); it is not related to open-source software or public intelligence.
History: The Foreign Broadcast Information Service (FBIS) was created in 1941 to access and exploit OSINT in relation to World War II. A classic example of their value and success is reflected in the price of oranges in Paris as an indicator of whether railroad bridges had been bombed successfully.
Sources (open) used in Maltego are search engines, DNS, whois record, PGP keyservers, open ports/services, historical DNS databases, social networks, etc, etc.
OSI have been around before then term was connected in popular media with software.
Application does not start...at all
- This is probably due to the fact that you have multiple Java installations on the machine.
- Workaround: To fix this issue, locate the maltego.conf file located in the etc/ directory of your installation. Uncomment the line that read
and replace it with the correct path to your Java installation.
- Alternatively it could be because maltego is trying to reserve too much memory
- You can set the amount of memory it tries to reserve in the maltego.conf file (in the /etc directory of the install). You might want to change the line that reads:
default_options="-J-Xms64m -J-Xmx1024m --laf javax.swing.plaf.metal.MetalLookAndFeel"
to something like
default_options="-J-Xms32m -J-Xmx256m --laf javax.swing.plaf.metal.MetalLookAndFeel"
Browser spawn on *nix platforms
- In some cases (and it seems totally random) there are issues with spawning an external browser. This seems to only happen on Linux platforms.
- Workaround: Go to Tools->Options and change your settings until it works.
Losing transform settings on discovery
- When you run the discovery wizard again you lose your current transform settings like parameters, keys etc.
- Workaround: none, we'll be fixing it
No transforms or seed servers on some Linux installations
- Under certain conditions the transform configuration cannot be written during the install process and you end up with no transforms.
- Workaround: Go to Tools->Transform manager and run the discovery process by hand. The seed server URL for the commercial editions is http://ctas.paterva.com/CTAS.xml and for the community edition it is http://maltego4.paterva.com/CESeed.xml. After the discovery process is done go to Help->About and copy your API key. Go back to the transform manager and put the API key into any of the transforms in the 'Key' detail. Save the transforms and you are ready to go.
Getting 504s (or other errors) on transforms
- Every once in a while you will see a 504 error when using a transforms. Occasionally you might see pop-ups with other error messages. This is when a transform misbehaves. We are working on sorting this out..
- Workaround: just click on OK to continue
Maltego slows down when running transforms on a graph with LOTS of entities
- As the entity count increase the graph library takes more time to decide where new entities should be placed. This should only affect you when working on very large graphs
- Workaround: divide your graph into smaller graphs and work on them separately.
Getting 'Yahoo API key exhausted messages'
- The Yahoo API is used for Search Engine transforms. Yahoo limits on API application key (that's not your key, but the server's key) and on IP number. This limit is set per day. When lots of people are running search engine transforms they key might get exhausted.
- Workaround: Wait a bit and then try again. Or - wait for a new release where client-side transform will be implemented (again). Also, try to set the slider to show less results. If you are getting this error message on a regular basis you should Contact Us.
Transform manager takes forever to start if client is not connected to the Internet
- When the client machine is not connected to the Internet the transform manager screen takes about two minutes to show. We're working on it...
Spelling mistake in the License Wizard
- When no license is present the message on the first screen of the License Wizard reads "". This should be "".
SOCKS proxies are not supported
- Although the options window allows for SOCKS proxies, Maltego will ignore them.
Pressing cancel on the License Wizard does.... nothing
- After the license has been received, even if the wizard is cancelled, the license is installed
Pressing Ctrl-A on large graphs causes the UI to freeze for a while
- When working with large graphs, the select all keyboard shortcut (Ctrl-A) takes a very long time. This causes the UI to freeze up until completed.
- Workaround: Until this issue is resolved, please use the mouse based drag select option when working with large graphs.
No Options menu in the Mac
The Mac options menu is located in the top application menu under preferences. The options menu can also be accessed via the start page.
Buy License link doesn't work on the Mac
The buy license link on the activation wizard is currently not working, you can however go to https://secure.shareit.com/shareit/checkout.html?PRODUCT=1 directly to purchase a license!
Local Transform processes do not terminate [ 2.0.2+ ]
On windows if a local transform is canceled or times out the process itself is not terminated.
Cannot close the nag window on the CE version at low resolution
When using a very low resolution (say 800x400), the nag window "close" button is sometimes not displayed, as a quick work around you can disable networking and then when the nag screen loads (after 15 seconds) select the "red" area of the nag window and then tab once (ie, press tab) and press space to press the close button.
Please Note: Maltego is best used at a higher resolution, and although you can use it at low resolutions it takes away some of the usability.
The Mac version does not have any transforms or is complaining about an API Key!
Unfortunately this is a problem with certain Mac installations, where the transforms and key are not automatically populated. Some Mac's may already have the transforms within the transform manager (tools->manage transforms) whilst others may not have them at all. For those with transforms, simply complete from step 2.
- To fetch the transforms, you will have to go the transform manager and select Discovery transforms - just remember to press enter after adding the url), click through the wizard (next,next,next,finish, etc). After you have completed this you should see the transforms within the transform manager. For more information on the Discovery process see 
- Select Help->About and copy your API key ( this is at the bottom, basically everything after the ":", should be something like 11111-22222-33333-44444-5)
- Go to the transform manager, select any transform, and in the bottom right window you should see a Key field under application properties, simply put your API key in here and then save. This change should be reflected throughout all of the transforms.
- You should now be able to use all of the transforms.