It happened before, and it has happened after update.
Please send Bug report to
support@virocoin.com with print screen + details, so I can reproduce the bug.
Still if this happen at block 30, the program save at block 24 (every 8 blocks) so you can't loose more than 7.
BTW - When a block is rejected mining Bitcoin you lose $7500 (The network is running for 6 years now)
The Virocoin network is only 3 weeks old.