Can Unimozer projects be opened in other programs?
Yes, Unimozer projects can natively being opened in NetBeans and BlueJ. No special changes or adaptations have to be done. Simply load the project via the menu "File > Open". I didn't test it with any other editor, but as most of them are able to import a directory structure, the import of the "src" directory should be possible in whatever other editor you use.
Yes, as it works very closely with BlueJ and NetBeans, Unimozer can natively open BlueJ and NetBeans projects. Attention: When opening a BlueJ project, Unimozer will change the projects directory structure upon the first saving. It will still be possible to open with BlueJ, but in that case you'll have to open the inner src folder.