Hi, I am moving to 64 bit. I have changed my project with custom server controls to 64bit also. We felt there was no reason not to move to 64 bit, as one of our projects needed to move for the memory access.
Tech used: Visual Studio pro 2013 Update 4
Since this point in time all custom server controls are now flagged with the warning of element is not a known element. and so intellisence no longer works in the webform/controls 
This worked fine with x86 until I switched it to x64 explicitly
I have reproduced this with a mock project. 1 Project with with custom control and and page with the control.
I have also cleaned, rebuilt, and deleted the schema. with the problem consisting
I've also tried just adding a @Register in to the page and still the same..
Web.config

WebConfig:
<?xml version="1.0"?> <!-- ***To set up a test database. 1. Change the ...

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