I was able to get 5 stones of experience through trading during the otto's box week.
I have TR'ed 2 sorc lives already using the stone (2 stones total). Currently, I am on my 3rd sorc life.
I have just hit lvl 8 and have tried using a stone. I get the message: (Standard): An error has occurred
I tried my 3 other xp stones and have received the same message.
I tried using the stone in inventory to no avail.
I tried using the stone through hotbar to no avail.
I made sure to click my character and have my character selected in the target box before I use the stone.
I have tried using the stone in different places such as the market and that did not work either.
The stone seems to be bugged.
all 3 remaining stones have texts identical to the text of stones from otto's boxes (so, they are not the old stones given out for free).
I am not sure what occurred as I was able to use the stone successfully 2 times already.
GM Bletchly told me to submit a bug report and I did that. I was wondering if I can get some help here as well.
I have attached an image of my stones and my inv.
Thanks for your help.