barkingcat,
Sorry that you are seeing issues.
Can you please answer some more questions for us ?
1. Please share the Installation Details from MyEclipse > Installation Summary > Installation Details.
2. If you have installed Android Development Toolkit, please make sure the version of the plugin is compatible with Eclipse 3.7 which is the base for MyEclipse 10.7.1.
3. Do you have any other third party plugins installed ? If yes, then please list them.
4. Can you try starting the MyEclipse IDE with -clean args and see if it fixes the issue? Did you also try a clean on the project followed by a refresh ?
5. If the issue persists, please switch to a new workspace, replicate the issue and share the contents of the .log file which is located at <workspace dir>/.metadata/.log.
6. Please share details about the project. If possible please prepare a sample project which exhibits the issue and send it over to help us investigate further.