Follow-up on the T-block issue. PC has re-opened and I spoke to Doug at the factory today about this issue. He was very helpful. He stated that the situation I have is normal; that the T-blocks are in fact designed to "float" so that they can make small adjustments to the slider. He stated that if necessary, one can access the heads of the bolts by removing small areas of carpet and flooring to create access under the sofa. I feel like I can rest easy now, knowing my slide-out isn't going to go off track!