Hi All,
Some good news; Davo, I don't need to send you error messages re the new installation because eventually I resolved that problem. There was stuff left on the system from a previous installation yet I could not find it. The error messages during the install via the terminal related to these items. A physical search of my system failed to find these files so, although not very experienced in using the terminal, I ran the install process again in the terminal and then, when an error occurred, used the 'sudo apt-get purge' command followed by the errant file name. Well the terminal found the file and removed it. I had to use this process at least a couple times more and then the installation completed successfully.
The next thing was to create a couple of simple test projects. This I did but after saving them, the problem I first reported appeared to resurrect itself with blank a form appearing (although only one but empty unit). I had tried to load the project from the project folder. Clearly that was not going to work so I tried opening directly from the Lazarus program using the 'Project' dropdown menu and opening 'Recent Projects'. That did the trick. So it seems this was my error all along and having not used Lazarus for a long time, I'd forgotten that was how I opened projects previously. It's puzzling though that this is not necessary on my Windows 7 setup nor, so far, on my other Mint system.
The culprit files were fpc-3.0.4, fp-compiler, fp-units-rtl-3.0.4.
One other thing with which I am not familiar but happens with my new installation is that when I first do a test run of my project I get the following message: 'The project does not write debug info in Dwarf format. The "FPDebug internal Dwarf debugger" supports only Dwarf. I am then given three options: 'Enable Dwarf 3 (-gw3)', 'Enable Dwarf 2 (-gw)' and 'Enable Dwarf 2 with sets'. So far I have used the middle option.
Well that's my update of the situation. Thanks for your support - I hope I haven't wasted too much of your time because the problem seems to have been due to inadequacies on my part. I'll give a few more days before marking the thread as resolved.
Cheers.