I've been working on a B2B SAAS product for the last year or so, and it's almost ready to launch.
I havn't done any SEO yet, however I did use BuildMyRank.com a couple of months ago, and during that time it worked quite well - made it to page 2 in google. As some of you know, BuildMyRank.com has since shut down because Google de-indexed all of it's articles.
Now, my site doesn't appear for any of the keywords at all. I'm not sure if it's because Google has penalized my site for using buildmyrank, or it's because i'm back at zero SEO-wise.
Given that there's a chance my domain may be penalized by Google, do you think it's worth re-naming my product (domain name) given that I havn't officially launched the product yet?
I would use the domain name you want the most.
If you find out you have been penalised by Google, you can always request reconsideration from Google (assuming you are no longer doing the thing you got penalised).
Request for reconsideration can be found here https://www.google.com/webmasters/tools/reconsideration?pli=1
It sounds like you might have been penalised, although it's hard to know whether or not you've been penalised by Google as they don't really make that kind of knowledge public unless your site is completely removed from the Google index (which would only happen in extreme circumstances). There are a few things you can do to determine if you'be been penalised though, they're not all definitive solutions but can help assist.
At the end of the day unless you've done extensive marketing I don't see any harm in changing the name, especially if it means that people will actually be able to find your product via Google.