Change CTRL-click to double click or right click for custom input

[islender]

I need to align a texture very precisely using the Transform options. However, dragging the sliders... ...either makes the texture go a little too far right or a little too far left, since the sliders change the values by set increments. I cannot figure out how to input a custom value into the text box. I've tried right click, double click, typing while holding left click on the text box/slider, increasing the GUI size and then repeating, e.t.c with no luck.

Am I missing something?

[islender]

Oh, I was just informed that holding CTRL while pressing does the trick.

However, this still seems like a strange procedure, most programs use either double click or right click. Could this be implemented?