My Pandigital Issues

[hopkins21]

Ok here goes......i just bought 3 of the white pandigital tablet/ereaders off of walmarts website (R7T4OWWHF1) for my kids for christmas, they have been wanting tablets so since they are 6,8 and 9 yrs old i figured these would be great starters. well the first issue i had was when we got them we wanted to download some apps for them that way they would already be on there for christmas morning, the only problem with that is when i tried to download the app (really any app) it says the memory is full or i am outta space (has 4 gb internal sd and 8gb external sd) and these things are brand new and dont have anything other than the factory apps on them, i even deleted the factory apps which freed up over 40mb of room and it still says there is no more room. i have also delted all the factory pictures and songs and videos and still it says i dont have enough room.....so any help would be great. i also tried to do a root so they would have access to the android market....tried 5 different firmwares and got white triangles on all, even tried without factory sd with factory sd and with external sd and still nothing. i know this is a lot for my first post but i just want to get these things up and running for my kids so any and all help would be great...thank you all for you time.