General :: How To Unbrick Prestigio PMP7100D3G Tablet

All information I found (perhaps I lookup with wrong keywords) is about unbricking the phone or other manufacturers tablets but once someone rooted the device and installed a modified rom but then playing with fastboot or some download managers, etc.

1. I wanted to revert back to 4.1 JB soft for my tablet as I found the most recent update messing up with 3G connectivity despite the fact the manufacturer prepared the update to improve 3G... anyway

2. I run the RKBatchTool 1.5 the device was connected properly as I did before when upgrading from ICS to 4.1 JB.

3. Unfortunately, just before the end of downgrading something went wrong (please see the below log) and now booting up the device fails. At first it displayed some linux script about trying to recover, then prestigio screen appeared just to show in a second a dead android robot with an exclamation mark.

14:57:28 504Rockchip Batch Tool v1.5.3.0 start run
15:02:16 091Rockchip Batch Tool v1.5.3.0 start run
15:05:33 769Rockchip Batch Tool v1.5.3.0 start run
15:58:23 292**********Upgrade Start Total<1>**********
15:58:23 307<Layer 5-3> Test Device Start
[code]....

4. I tried a combination of volume up and power button but still no luck.

How can I bring the live back to the device that was not rooted. I have an external SD card. I loaded an original image from prestigio but I guess I need something else done so it actually boots from the SD and recovers the ROM to the internal memory.