Problem in MTS-ESP tuning

The latest version of Pianoteq adds support for the MTS-ESP tuning method for the excellent new tuning plug-in from ODDSound. I believe this uses real-time MTS. As opposed to multi-channel pitch bend tuning, this method creates problems with a physical-modelling instrument such as Pianoteq: if the changes in the tuning are significant such as in the case of more notes per octave than about 20, the sound gets severely distorted.

Normally, selecting Full Rebuild would be the remedy but when Pianoteq is in the MTS-ESP Tuning mode, the String Tension / Full Rebuild button has no effect. Is this a bug, or is it actually impossible to program the instrument so that Full Rebuild would work? At present, the MTS-ESP method is all but useless, and polyphonic pitch bend has to be used with the MTS-ESP plug-in even if that means only 16-tone polyphony, which is not much for a piano instrument.