Jumping curser

I have had a problem with a jumping curser for a few weeks now. I have made sure I have updated, etc., but cannot get this curser to stay put. I’m in proofreading mode now, but can’t trust that these random letters are not going anywhere between the normal text window to the corkboard area.

I recently purchased a new computer and received a download link from Scrivener, but something has been unstable this whole time.

How can I tell what “version” I have of Scrivener? I have a serial number but think maybe I need to update?

If I choose to purchase the latest one, do I have to uninstall first or will it download right on top of my present software? Is there any risk of losing my work?

I searched around for “curser” in the help sections, but don’t see anything about a jumping curser.

Thank you, Regina