When I tried using it my character vanished and I couldn't switch to the gear girl. also would it be possible to get this mod working with the character helper mod?

1) What do you mean by your character vanished? Was it just invisible but you could still walk around, or did you get put into the spectator camera and lose all the stuff in your inventory? If you were using a different skin before installing this mod, try disabling this mod, switching back to the default engineer in your save file, then re-enabling this mod.
2) I'm currently working on an update for Skins Factored (the library this mod uses) that should improve compatibility with CharacterModHelper.

I think I might've figured out why your character vanished, and I uploaded an update that should fix it (version 1.1.2).
EDIT: I also updated Skins Factored to work with CharacterModHelper now.

sorry for such a late response. the recent updates solved the issue but I can't select the skin in the character selector

What do you mean by you can't select the skin in the character selector? Does clicking on any the buttons do anything (change color, print a message, crash, etc)? If it's saying you don't have a character, you might be stuck in the spectator camera, in which case you'll need to load an earlier save before your character vanished.

the vanishing character issue is fixed there's a new problem where gear girl isn't listed in my character list.

Is there only one button (for the engineer) in the list? Make sure the Gear Girl 2.0 mod is enabled and updated to the latest version. (If there's multiple buttons but the character preview is just a black rectangle, the button should still work; this was caused by a Factorio update, and I'll fix it today).
What happens if you run the /character command in chat; what gets printed out?

it says: currently running in compatibility mode with miniMAXlme, please use it to change your skin
!skins is providing the following skins to that mod: gear-girl.

Oh, I didn't realize you were using miniMAXIme as well; does minime's skin selector not show the skin? There were some issues from 1.1 that I don't think me and Pi-C ever got around to fixing.
If you don't need the character-resizing features of minime, you can also just disable it and use the already installed character selector from !skins (skins factored).

I disabled minimaxlme and it's all working fine now.