Sounds like you need version 3.4; the only way I'm certain about installing an older version of an app is with an iTunes backup (but maybe someone with more experience than I have will have some ideas).
I have a question for you: One of our engineers was helping someone having a similar problem (freezing and crashing) on the same device and there's was directly related to their wireless connection. It wasn't a good one. How is your wifi connection?
My wifi is fast and stable, and I've actually been having a similar problem with a couple of non Adobe-related apps because of how old my device is. For example my YouTube app has become "too good" for my iPad to process, so it lags and freezes while working perfectly fine on my iPhone 6. So I believe the problem is just my outdated tablet.
Yep. I totally understand, older devices with newer software can be problematic, I just thought I would mention it because it seemed to change the drawing experience for this particular person.