I downloaded the wallet from the website early last month.  I'm using v3.4.0.0, which seems like an earlier version.

I'm sorry if my question seems dumb since I'm fairly new to this. Should i change to the new wallet now? Or will it be okay to use the older one?

I got 500 coin rewards a few times (about every 3 days), but then I added another deposit which doubled my wallet size (>1million); however, the rewards stopped. None for the last 10 days even with the wallet unlocked and kept open.