If you want to have power to your tablet and USB OTG access at the same time, here is what you need(both Amazon prime eligible):
http://www.amazon.com/gp/product/B00...?ie=UTF8&psc=1 (Any usb gender bender like this will do...there are cheaper ones)
Attach the USB gender changer to the black end of the StarTech cable and the attach a USB hub to the other end of the gender changer. Plug the red end into a 2.1 amp USB power source and the microUSB end into the Encore. Now the tablet will say "plugged in, not charging". You can now attach any USB device to the hub and Windows or Linux with see them. The tablet will have power but the battery will not charge.
BTW another question. Why card reader in this tablet is that slow? I have sandisk extreme micro sd (64MB/s write - ~ 60MB/s in my PC card reader) but reader in toshiba can only read/write ~26MB/s. I thought that this card will be great for my tablet, but now I fell like I wasted my money. I could better buy standard class 10 micro sd card...