Canceling quick cast indicator with R mouse click is annoying, disable available?

As a pretext, I love the quick cast with indicator. Being a player of LoL for over a year now, I'm playing more and more champions in other positions now that I feel more comfortable. I have branched out from support to mid lane and top lane with an emphasis on mid. My inquiry is that which is stated in the title. My issue is when I play Orianna, and I'm slowly learning her role and range for abilities, it would be nice if I didn't cancel my indicator with right click. Hell, I'd even like it if I could map it to the left mouse click, so that I could move around with her ability held down and release when I wanted to. Alot of people would say that I could go back to smart casting or normal casting, but either don't give me the perks the smartcasting with indicator does with someone thats learning a new champ. Yes it takes work and time to learn a new champ and repeated matches will allow me to understand it easier, but it would be so much more enjoyable gameplay if there was a way to map out the Right Mouse Click cancel for the quick cast with indicator. And for someone in midlane who moves constantly, canceling on Right clicks makes the indicator not reliable, especially in team fights where buttons can be mashed and you're repeatedly trying to juke but your abilities may get canceled if they are pressed inbetween a Right Mouse Click to move.

My question is: Is there a way to re-map the Right Mouse Click to cancel smartcast with indicators to a different button, or is it stuck that way :(?