>It could be the value of your text1.Format property. If .Format = "R", I know the text.Value will not include the mask. So maybe selstart doesn't change when you pass a mask character such as "," or "."
I didn't put anything on text.format, what I meant is if I press left/right arrow passing the value in text1 (assume it has a value=150000 and displayed 150,000.00, and text1.selstart value would be visible on text2) and when the cursor pass ',' or '.' which is already on text1, the cursor will jump.
As example,
text1.inputmask='999,999.99'

when text1.selstart=2 and right arrow is pressed, text1.selstart will jump to 4 and cursor on text1 jump to after the 1st comma.