how to use Google's TranslateGemma ? (oMLX says Chat template error)

got the translategemma-27b-it-4bit MLX from LM Studio Bionic (latest oMLX doesn't let me DL from Huggingface) on my ARM mac.
Apparently you can't use natural language prompts in this app (at least with this model), which makes it a bit hard to use.
Found some instructions here :

https://github.com/ml-explore/mlx-lm/issues/783

but using awni's template still gives me the same error :

Error: {"error":{"message":"Chat template error: User role must provide content as an iterable with exactly one item. That item must be a mapping(type:'text' | 'image', source_lang_code:string, target_lang_code:string, text:string | none, image:string | none).","type":"invalid_request_error","param":null,"code":null}}