You are right. my posts tend to cause some misleadings to the reader, I apologize for these posts and you can delete that post directly. It seems that the BTCert project is trying to solve technical problems itself but not Blockcerts for the reasons that:
1 So far, the issues such as certificate revocation and issuer identity had been solved or are solving by the Blockcerts.
2 I have not forked and submitted the Blockcerts code, from this point, I can not say I have fixed Blockcerts problems.
BTCert is only a mini project for my master degree and has no commercial use. My original intention is to promote the Blockcerts and try to persuade our university to use but failed. In my next plan, I will try to add the multi-signature function for the Blockcerts as a component if you welcome.
Lastly, since BTCert is sponsored by ITIC University of Birmingham, I will ask them whether it is ok for me to publish the code, I will release them as soon as possible once I get the permission.