Ubuntu 64bit - works with errors

After the previous version stopped working saying licence expired I downloaded the new version, modified the .deb file to enable installation in 64bit Ubuntu and reinstalled. All seemed fine except that it will only work on one document at a time, i.e. the default blank drawing must be closed before an existing drawing can be opened otherwise the DraftSight drawing window freezes. On starting DraftSight a new drawing can be created and saved, but it must be closed before opening or starting a second drawing.

The previous version work perfectly using an identical installation method but despite deleting the SWActivation folder, attempts to reinstall the old version result in the licence expired message again.

Any pointers on how to remedy the problem in this latest Version V1R3.2 when running in Ubuntu 64bit would be much appreciated.