You suggested is true. Error 7 has long been known, and the solution is very simple:
1. Change tvrp
2. Transfer firmware verification checksum.
3. Firmware is downloaded not to the device.In the second embodiment additional information.
I do not know how Masik (not used at the office and firmware source did not go), but many kastomizatory and romodely spread checksum firmware file. Must be compared with the file available to you. As often happens for the firmware downloaded from the error, or when copying is copied with an error (for example up to OtgFlash)
For comparison, hash sums, there are many programs in the Market.