Though I try to avoid public variables, 10 won't kill an app.
Since 1GB is only half the limit, that shouldn't be the problem either, then let's round up the usual suspects
1 - though the aout of memory error probably doesn't relate to this, the behaviour of deleting lines/letters in the editor can occur based on having a form open which utilizes the timer function
2 - some hardware related stuff related to your computer or network
3 - some kind of corruption - there shouldn't be anything stopping you from at least trying some of the tips and tricks for working with corrupted dbs - start with taking some copies of the db, and keep the original, in case you'll need professional/paid assistance.
Here's some text I'll sometimes drop into threads were I suspect corruption might be an issue:
"This faq
Corrupt Microsoft Access MDBs FAQ has a lot of info concerning corruption, symptoms and how to deal with it. MakeItSo's FAQ705-4683 also has some recommandations.
During the last years, I've resolved all my code corruption issues using the /decompile option, in stead of importing objects. It's described here
Decompile or how to reduce Microsoft Access MDB/MDE size and decrease start-up times
Here's also an option that might provide some results on exporting/importing database objects Thread705-834817."
There's also a utility which is downloadable from Microsoft called JetComp (which I've never tried)
Roy-Vidar