I don't use nor am I familiar with you're type of touchscreen,
however, if there is an answer it is related to these links.
http://www.autohotkey.com/forum/topic6367-45.html
http://www.autohotkey.net/~Micha/HIDsup ... otkey.html
http://www.autohotkey.com/forum/viewtopic.php?t=43732
http://www.autohotkey.com/forum/viewtopic.php?t=30245
Also do a Forum Search on "Touchscreen" or "Tablet", you'll find others.
Have Fun,

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