Dear Dr. McLaren,
I have tried many times whole day but still can solve this questions:
This is the error information:

%%%%%%%%%%%%%%%%%%%%
Estimation Failed
Warning: Missing conditions!!! Invalid Contrast
Invalid Contrast
Warning: Missing conditions!!! Invalid Contrast
Invalid Contrast
Warning: Missing conditions!!! Invalid Contrast
Invalid Contrast
PPI Contrasts were not estimated for some reason.
%%%%%%%%%%%%%%%%%%%%
After that, I type :SPM=spm_estimate_PPI(P.subject,'SPM.mat',P.Region,P.method,P.analysis,P.CompContrasts,0,[],0,0);
the error was reported as:
%%%%%%%%%%%%%%%%%%%%
Error spm_estimate_PPI (line 290)
SPM.xM.TH(:)=SPM1.xM.TH(:);
%%%%%%%%%%%%%%%%%%%

I debug the spm_estimate_PPI line by line, and the SPM.mat estimated from the PPI did not contain the SPM.xM, could this leads to the errors?
I have tried other thing, such as change the P.contrast, change the onset name to short, all these did not work...
Could you please help me with that?
Thanks a billion!

Sincerely,
Xinyuan