Hey there. Congratulations on getting your GCW Zero unit!
UMG is nicely done even if something isn't quite right with the spikes on the first level -- they're very hard to avoid so I think the collision detect/hitbox might need work.
I'm one of the developers behind UMG. I am quite curious of your observations. Let me explain how collision detection works in UMG:
A) The top rectangle shows the spikes tile, as seen in-game. The bottom rectangle is the actual collision area of the sprite (red -> damage, white -> no damage). Collision detection is pixel based, that is the player's collision box needs to intersect one of the red pixels.
B) Player standing a pixel away from the damage area.
C) The collision box around the player (taken directly from a debugging build of the game).
As you can see on the above picture, the player's hitbox is smaller than the actual character (in walking animation). Additionally, collision with the scenery is done on per-pixel level (and not per-tile level). The player's collision box *must* intersect the red area for collision to be registered. For player velocities higher than 1px/frame (ie. while falling), the collision calculation is split into smaller steps, to make sure the intersection is registered at the first possible pixel. So I think we can be talking about a very accurate collision detection model.
Now, the game runs natively in a 160x120 resolution and is upscaled by a factor of 2 into GCW Zero's 320x240 resolution. This means that a single in-game pixel equals 4 pixels on the GCW Zero's LCD. This could give an impression that the movement is calculated with inaccurate precision, but there's nothing that can be done about it.
Please also note that UMG is a game with deliberately high level of difficulty (hard, but fair). If there is any unfavourable placement of the spikes, it is probably because the level designer intended so
As for your remark about using the reset button - please keep this as a last resort. Pressing the reset button abruptly cuts power to the device, which might result in data loss or even filesystem damage! If you think that a game froze and you want to kill it, use POWER+SELECT button combination instead. This kills the program and returns to the menu, without destabilizing the operating system.
You mentioned a hang on start-up: both the firmware and all the software present in the official repository (repo.gcw-zero.com) is tested for stability and we make sure there are no situations that prevent you from exiting the given program.
Could you share more details about the hang up problem you had?
And as @Senor Quack
above mentioned, feel free to join our IRC channel
. I am sure we can help you with all the problems you are facing and answer any questions you have