My Question was "can a NEW "Room Type" be added?" According to Nathan B., in technical support, the answer is; NO, users of HD pro 2023 may not add new Room types. The number of room types is fixed in the program. My copy of HD Pro has 32 Room types.
We discussed two example bedrooms; One with hardwood floors and one with carpeting. In this example Nathan agreed with Rookie65 in that a given named Room Type; "bedroom" in this case, can be first used in one bedroom to specify, for example; a hardwood floor, and then the same named room type can be modified for a second bedroom to specify carpet. The differing attributes are stored in the design file. The default floor for the named type "Bedroom" remains Carpet unless and until changed by the user say if a new Design is started and there is a need for hardwood flooring again, or perhaps to apply tile to a third bedroom in the first design file, Nathan also agreed that for a given design file an unused room type such as; "Bonus" or "unfinished" could be renamed in effect providing a second bedroom default, However, the total number of Room types does not increase only their names change and related attributes when changed by the user.
Nathan also investigated and found that earlier versions of Home designer Pro, as shown in the training videos, indeed had multiple bedroom types; Master, bedroom 1, bedroom 2, and so on. These were eventually deemed "redundant" and removed, they are now not delivered with current versions of the program.
Thanks to each of you for your support, and David, Thank you for your quick Video it was very enlightening on changing attributes on the fly, and especially the part about Display options I will be paying closer attention to that.