I haven't been able to grab a chance to find out.

I did take some time to process the Yandex tardumps into a git repos: https://github.com/datacoinproject/datacoin-core (08 is the last, I lost track during the flurry of Windows fixes). Might be worth using that as a base to explore testnet issues.

I've also contributed an in-wallet block explorer (fwiw) in a separate branch: https://github.com/datacoinproject/datacoin-core/tree/feature.blockexplorer - the community can decide collectively whether it's considered to be worth the maintenance effort to include.

Cheers

Graham