Hi, thx for reaching out!
Scrolling the time while paused is indeed something I could add (putting it on the trello board), not moving it via a connected device is deliberate however; it could cause synchronization issues that I'd rather avoid.
Concerning the issues you have I'm very interested to fix these. I am however unable to reproduce the behaviour you are reporting. Could you help me out and send me a Player log of a session where you tried and failed to click on the buttons?
You can find the player log in this location:
%APPDATA%\..\LocalLow\AvaDev\HPTM\Player.log
You can mail me a at alex.vandenabeele[at]gmail.com
Maybe I should ask: what resolution are you displaying at? (Shouldn't make a difference, but you never know)