Well, some of us translate the T as "transsexual" which, more is more commonly defined in the sense of a person with the brain/mind the opposite of their biosex. This is different than G L &B although a TS is technically homosexual, in the bio sense, its distinctively different from a typical gay whose mine matches his body but still has an attraction for the same sex/gender.
Some folks use T or TS as a catch-all for any behaviour of condition than involves unconventional sexuality ----But I think the folks that contrived the G L B & T had the first definition above in mind.
A CD is likely to be hetro (although some TSs dress to suit their mind) but those are for different reasons all together, Some gays may also CD, but for the same reasons hetros who's CD is not sexual, do.
Really, though I never could figgure out the Gay /CD connection. It dont make sense to me--and gay "Drag" shows? why? Gay guys are supposed to be attrected to other guys and other people who LOOK like men. It just dont make sense. One of those mysteries of life I suppose.---My only explanation is perhaps its the TS folks that do the drag shows, and make up the bulk of gay CDers, yet TS people are not quite the same "animals" as are regular gays .