Phil,
A suggestion might be to contact Mr Pike with your concerns if you have not already done so. I cannot speak for Lindsay, but I can say that if you had recently purchased a captive bred uromastyx from me and were having some concerns, I would certainly rather have you come back to me for advice than post for answers on a forum. Not knowing there were any concerns to begin with and then hearing later on that the animal eventually went downhill because you took the advice of others, would probably have me quite frustrated.
You may have already contacted Lindsay and if so, then maybe the only purpose this post will serve will be as a suggestion to people purchasing uromastyx that they should probably follow up first with the person they purchased the animal from if concerns surface within a short time frame of purchasing the animal.
Most reputable breeders are eager and willing to help out when concerns arise and many consider this a part of their service. This little perk (support) is just one more reason to invest a little more money in a captive bred animal with a reputable breeder. I guarantee you, the cost is almost always less in the long run.
Could this be a normal phase the ornate is going through- sure. But it could also be a setup issue or a different stressor which could eventually have an impact on the health of this animal. My suggestion is to give Lindsay a shot at helping you to correct the situation (if one exists) or in alleviating your concerns. Second opinions on forums are great but I can tell you where my preference would rest when looking for answers.
One last suggestion- you mention that your room 'probably' does not get to under 75. I suggest that you measure all of the temperatures - day and night- gradient and basking. This will help others (whether it is Lindsay or this forum) when giving advice.