homebrew laser engraver with arduino uno and laser gbrl

Hi all,ive built a laser engraver using the above with linear rails and nema 24 steppers ,in using gbrl 1.1e and trying to use lasergbrl,the issue i have apart from the program hanging freezing etc is : if i try to engrave an image of say 50x50mm after setting the start position after a few mins the machine is way off as in its almost off by 2x the size of the work,also the laser stays on when the motors stop,another thing sometimes when trying to engrave the cursor on the pc screen is stll moving but the steppers have paused with the laser on then after maybe 4 seconds they resume,im using  micro stepping and all the steps per mm are good,any ideas?,its driving me nuts $32=1,seems lasergbrl is a big fail to me so far!,can anyone point me in the right direction other than throwing it all in the rubbish bin?,cheers m3vuv.

Well i tried a gcode test file i found on here,that works fine,i will atach that along with a png file of a horse that doesent seem to convert right,could someone try and convert it to gcode for lasergbrl for me so i can see if that works,then i can tell if its my setup,cheers m3vuv.well i was going to but see no way to attach a file wtf!