onejube

I'm making a game...
I've added an object to the floor that's after the start up screen to enter into game-play (level 0). The problem is that in the game the image is in the right spot but the actual selectable object that has the event "left mouse button released" is just below it and you have to select underneath the image in order to activate the event. This happens to every object that's below halfway in a room, the selectable part is underneath the image which is really unprofessional. Is anyone able to help me with this? let me know if you need anymore information.

On a side note, any ideas for a system that;
randomises the next unit that is sent at a random time (between 1-3 seconds). After 60 seconds (a round/level) is up exactly 30 units have been spawned that are divided up into 3 groups. 7 type A units, 14 type B units and 9 type C units, with those conditions met i need it to be random so the player is unable to predict the next type of unit.

Thank you in advance.
It's nothing to do with masking

Self explanatory, I've purchased GM 8.1, as i open it after installing i receive the following error message "List Index out of bounds (1)." WTF do i do? I need this program quite urgently on my laptop as I'm using it to do a class project.