K5synth

Hi. Having a lot of trouble properly getting patches into my recently acquired K5 for some reason. Memory protect is off, Sysex on. Have tried Kfuenf, MIDIox and C6. Multi patch names seem to load but of course without the corresponding singles they don't sound right. With Kfuenf sometimes the first patch will load but then stops. If I try to send patches individually some will work, most fail. Can't figure this out. Advice please!