Don't interpet your sensation of "warm and humid" to mean there's a mysterious humidity problem,it might simple be warmer in the room. Test humidity with a hygrometer. If indeed one room is drasticly higher it's a matter of finding the source of moisture. Bath,laundry or kitchen vent dumping into wall/attic is one possibility. Laundry dryer not vented outdoors is one. Invisiable roof or plumbing leak is another. We could go on forever but on site investigation is what it take's.

Echo the advice to get some instrumentation to look at humidity. 35% RH is scary low and cannot be necessary for wood floors unless something is wrong with the floors. Do you live in an arid area? If the room is truly excessively humid, you need to find out where the humidity is coming from.

If the problem is localized to the floor vent and the windows, that is where the humid air is coming from if it is humid outdoors and on the other side of the floor vent. What is under the floor, a crawl space? Is it humid under there?

You might need to seal around those items, but chances are that this room was done the same as the rest of the house. If air is leaking into that room specifically, the next question is why? It may have low pressure due to design of supplies and returns. Where are your returns? Are the supplies all open in that room? Is it less humid in that room if you leave the door to the hallway open?

Thanks for the input - we will definitely get a hygrometer to verify the humidity. The humidity only seems to be in the area surrounding the floor vent (which is right below the windows). When you walk over to that part of the room, it suddenly feels humid (similar to an indoor pool) and that is also where the paint on the window sills is peeling. There is slight peeling on window seals in other areas of house but very minimal except in this area the frames need to be repainted as most of the paint on those bedroom windows are peeling (less than 1 year occupancy). We are wondering if the fact that the steam injection humidifier which is in our mechanical room directly below this bedroom (2 floors below but same location) is not balanced and that vent is getting too much humidified air flow). Basically a volume balance issue. Our HVAC technician disagreed.

If you are buying an inexpensive thermometer/hygrometer, get two so you can check them against each other in case one goes bad. You could just get one and buy a decent sling psychrometer on Ebay for periodic checks. They are easy to use and the most reliable check on the electronic ones. The electronic versions can be off and you can't tell. With old-fashioned physical/mechanical instruments, you either get a good reading, or it is obviously broken. Actually, you should probably have at least two so you can monitor in at least two places without waiting for a single instrument to equilibrate. First, compare them side-by-side so you can make a correction for any difference.

I highly doubt that your "feeling" is misleading you. Human senses are among the most sensitive ways to measure things, though sometime cumbersome to put on a quantitative scale. The peeling paint confirms a problem anyway.

"We are wondering if the fact that the steam injection humidifier which is in our mechanical room directly below this bedroom, Our HVAC technician disagreed."

I believe everyone will agree this is something that should be looked into very closely. How close did your technician check it out and how good is the technician? I can't give you step by step instructions since I can't see the situation so just use common sense and process up elimination looking for air leaks and such in mechanical room.

Is that steamer running a lot of the time or only when the HVAC is running? Either way, with the room right by the air handler, there needs to be some form of balancing. Is the air very powerful on that vent when the unit is running?

Concerning the window peeling, it could be condensate on the inside of the window from the high humidity if it is the HVAC, or it could be the window is leaking and causing the humidity problems and you have moisture trapped in the wall and future mold issue.