I haven’t seen any issues myself. First we need to see if theres an error with Optimal itself or if your client added custom code which caused the error. Can you ask them to see if the Optimal demo shows up in IE10? (I’m actually using a mac so I don’t have an immediate way to check on a PC)
As far as updates go, Wes is re-developing all of his themes to work with Genesis 2.0 and HTML5 (which should be released as soon as WP 3.6 and Genesis 2.0 is out). So that means major updates to enhance the entire theme.
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