By a fluke I allowed MacKeeper to update iCash to the latest version & installed it, not realising it was not an update but a paid upgrade. I had v550 which is perfectly fine for my needs.
I re-downloaded and installed it, so far so good; but when I click to open my folder I get a warning "this file needs a new version of this software to be opened".
Well, I am afraid I don't quite know how to deal with that: could you help?
Many thanks,
alicia

When you open an iCash file with a new version that uses a new database structure, the file needs to be updated. iCash displays a warning window about that fact so you can cancel. If you clicked Ok you asked iCash to update your file to the last version. As a result only that last version can now open it. The solution here is to use a backup file. iCash creates backup automatically. It is explained in the iCash manual. It says:

"In addition iCash also performs automatic backups for you to the ~/Library/Application Support/Maxprog/iCash/Backups folder every-time you close a document or open a document that needs updating. Each document backup is saved to a folder with the same name. Only the 15 more recent backup files are maintained. They are labeled with the backup date, for example '2005-10-13 19-43-09' which means 'October 13, 2005 19:43:09'. In addition iCash also performs redundant XML Backups to the '~/Library/Application Support/Maxprog/iCash/XML Dumps' folder."