When I look at this game on your author page; it says the game is for sale for $1. when I am looking on the game page only the free demo is available. is there a purchasable version like your other games currently?

not yet, the game is still under development.

You may become a tier2 patron ($5) to early access the alpha version. 

The game will be posted in all platforms ($1) once it is completed.

Noted that saves in alpha version may not compatible to the latest version.