maybe the program makes the songs for longer then 30 seconds?
best way to do it if your jailbroken... itunes conver to aac then rename to .m4r as you done then in openSSH upload them to the ringtones folder..
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the way your doing it should be fine if you add to the ringtones folder, not in the iphone tab ringtones add to library then in the iphone ringtones tab select chose what tones to have and select them all, i hope that makes sense