I have prepared a test executable of Blastaway that tries to solve the problem of D-pads being seen as analogue devices - it simply accepts also joypads that are reported to have only thumbsticks and has some additional code to handle also analogue input.
Could you try it out and let me know, please? The executable can be downloaded from https://www.retream.com/_temporary/Blastaway.zip and simply needs to be put in the game's folder.
EDIT: forget about the test executable and download the updated game, instead ;)