Firstly, if you have overheated it, then there is a good chance the engine is about gone. The aluminium rotor housings would have warped & gone out of spec. this would then allow water &/or oil into the combustion area reulting in difficult starting & poor running. Compression would be down too.
The 2nd issue you would have should be a simple case of Cosmo flooding. happens if you turn the engine off without properly warming it & driving. The worse the condition of the engine, the easier it is to flood. Un-flooding it is anything from tuff to easy. Depends on what you know, who you are & if help is at hand.
Where are you loctaed..........??