1. Fix a problem with the field attribute sealing logic in MSBOXX (and related routines INMEMO and PCKLST) in which attributes to the right of box would sometimes be changed incorrectly by box drawing.
2. Remove three second delay on "program not found" error.
3. (Windows) Warn user when original file cannot be overwritten by updated work file because it is in use by another job. (This would occur when a second job has the file open for read-only.) Now gives opportunity to fix and retry or manually fix.
