Xmouse1 and xmouse2 acting as Shift and Ctrl?

Hello everyone, i need some help figuring how can i make my two on the side buttons act as shift and Ctrl to use my hotbar more easily because right now i can only use 1-5, Q E R T F C, Alt+1-5, Alt+ Q E R T F C..... And i need more potential combination to be effective, 22 is a bit low with all skills + potions.
Befor you say something like: why just you don't use the Shift and Ctrl on keyboard? Let me tell you i can't my little finger got crush and nerves in my little finger are practically dead(can barely moving it).

What i'm looking for is a little open source programe that let me mapping the mouse(legit and don't need be ultra complex i just want to put shift and ctrl on my mouse) or a way to change the way windows detect xmouse1/xmouse2 from page up/ page down to Shift/Ctrl with some sort of permanent key registery.

So far i try get the official app for my mouse but my mouse is too old i have an Minosx1 and needed at least Minosx3 to use the app.
I also try x-mouse button control but from what i seen it seem to only work on desktop admin lunched or not... I read somewhere that x-mouse used to work in FF14 in the past... X-mouse seem to work for one click in FF14 after that it seem the game blocking x-mouse or have some sort of force out defaut keyboard build-in. X-mouse is bannable?

If you guys use an 6-7 buttons mouse with build-in app with the remapping working in FFXIV, i'm all ears i may change of mouse if the price is decent or if is too much problem find an programme that let me do it with any mouse.