An unsigned int (4 bytes) will be just the same as a signed int, up until the signed int max value, right? Or do you need to do something else to poke an unsigned int?
Poking is no problem, if you are ever printing or using unsigned ints in blitzmax calculations you may want to convert them to longs like so:
Function uint:Long(value:Int)
Return value&$ffffffff:Long
End Function
myunsignedint:Int=$ffffffff
Print myunsignedint
Print uint(myunsignedint)