Hello. I'm not aware of the glitches and bugs, as much as I know the v0.1.2 does not have any level-up bugs or etc, and it's been out there for almost 4 months.
I think you're talking about the HERO EXP LEVELS, the top blue thingy, right? Well, if you open the perks menu and buy a perk that needs, for example, 2 levels. Then, if you're level 5 you'll lose 2 levels. And you'll end up with 3.
And can you explain a little more about the forwarding and backing glitches?