Most of those models at battle clinic are in sfc .mod format you would first need to get premission from the author of the model to convert it then you would need , milkshape , max3,4 or 5 or gmax to convert the model to obj format . Then you would need xsi to convert, remap and hardpoint the model to get it to xsi format for the sins .mesh conversion. And they said the game was easy to mod ha ha 
Oh and i think if the model has more than 1 texture and its not square ie 512x 512 then the model needs to be remaped with just 1 texture map to show up in game and its got to be converted to dds ? Correct me on this if i am wrong please anyone.
And no porting is ok if you port a user made model alot of modelers like me will allow porting/converting to other games if you ask premission to do so first. But most game company models it is Illegal to port if you read the licence agreement it should state what you can and cannot do with the content of the game in most cases you cannot convert the stock industry game models.
