Shields are capped at 2 bars right now but gaining any over that will store the +. There is at least one upgrade that costs shield bars so that hidden +1 is still useful (it isn't really hidden as it is listed on the modifiers list in the pause menu).
Teleport pads being invisible is a bug that was recently introduced.
There are some mobs that don't move until you get close or hit them at least once.
If you feel like something is absolutely buggy or wrong then throw it up on Mantis for sure!