Thanks! Much appreciated the feedback!
So for 2.: Could it be that there was still a pair of yellow besides what you were trying to match? If so you must match all the pairs of hidden blocks of that specific color (there are 2 pairs plus 1 hidden plus hidden bottom/base block) before you can match the remaining one with the corresponding block, that's the rule... I explain all the rules in the ?-section (you can click the slow blinking to change rules), but anyways I should explain the rules better and more direct (maybe I will add a skippable tutorial as an intro if it's the first time someone plays the game). If it's not the case I need to look for some bugs!
For 1.: That's interesting, this one seems not to be related to the infamous rules XD... never happened to me... I stop swapping the ability of a block (meaning press and drag in a direction, between two activated blocks or between one activated and one deactivated) only when that block is animating, so maybe I messed up there!
Thanks again for the feedback!