I have been programming midi for many years and I am currently authoring SP content professionally.
Recently I have come up against extreme difficulty in getting files to open in the above named handsets (Nokia's 4 note range).
I have read many, if not all of the published documents on SP midi that are available through the forum. I have tested exhaustively on the 6100 and although I can get files to work eventually - I cannot define exactly where the boundries lay between a file working and not.
It was my understanding, especially after digesting the notes from seminars by Mr.Dolby and the like that a 'one size fits all' approach to authoring files was possible using SP midi - This, in my opinion is clearly not possible without seriously compromising the quality of ringtones.
It appears to me that the problems with these phones are not file size related - I've had some success when reducing the amount of program change messages that I've used, but due to other tests that I've done - I know that there's more to the issue than this.
Please can anyone tell me where I can find advanced technical data on the 6100 and/or the 3510's synth capabilities - particularly regarding limitations.

Thank You.