Is it Arduino compatible? If you can upload to it from the Arduino ide you should be able to use it in embrio. Embrio doesn't really care about what chip or Arduino model you are using. Version 1 had a list of available pins for each model but version 2 doesn't do that any more, partially for more flexibility. There is a setting on the Arduino options page to not use the last setting from the Arduino ide and instead it puts together an upload string based on the model you have selected, but there's really no reason to use that and I'll probably get rid of it at some point. The only concern you might have is that timing is saved per ardunio model, but that shouldn't be an issue for you now. I will probably remove the ardunio model selection at some point or add a "misc" option. For now just select anything it shouldn't make a difference.