Part of Drawing Not Printing

I have been using Draftsight for some months now and was doing a drawing for an operating manual when I ran into a printing problem which has me stumped. After I upgraded to V1R1.3 I found it to be quite buggy, so uninstalled and went back to V1R1.2.  As far as I know the activation code is still OK but most of the drawing was done while I was disconnected from the internet. I think this meant I was running the program without an activation code for a while.

Now I find that with this particular drawing any lines, text etc. show up OK on the screen but will not print, either to PDF or a printer. Content that was done earlier on the same drawing prints OK.  New drawings and others done previously print OK as well . I have tried copying into a new drawing (via Windows 7), changing layers etc. etc. but to no avail. Any suggestions on how I can recover this drawing would be most welcome because at this stage it looks like 6-8 hours of redrawing will be required.

I have redownloaded V1R1.2 and reinstalled but haven't been asked to activate it. I would prefer not to install V1R1.3 due to bugs with Esnaps etc.

Many thanks.