Please could you consider allowing FindImagePOS to accept an optional parameter to be a colour in the needle file to not compare to the haystack.
ie, permit a bitmap like
..........
..xxx.....
..x..x....
..x...x...
..x....x..
...xxxx...
where "." is set as a non-checked colour, enabling a match to any location where the x's are a match.
Yes, I know ascii art doesn't reallly work here, but I hope you get the idea