After reading several MAW Trip threads, I noticed that there might be some confusion about the GKTW GAC.
The GKTW GAC is the only one that is meant to expedite entrance (hence the green light). The idea is to expedite, and there are situations where you will have to wait. For instance, if the ride has FP, you will go through the FP line. If FP is backed up, CMs may bring you up the exit since the idea is to expedite whenever possible. I can't guarantee as this is up to the individual CMs and the ride. If your child is travelling with a WC, you will have the option of waiting for a special ride vehicle that accommodates WCs. Most attractions give you this option (so you can choose to board immediately instead of waiting), but certain attractions don't, such as Kilimanjaro Safaris. If you go up the WC entrance there, you will have to wait for the WC car since it is a separate boarding area.
For smaller rides without FP look for the entrance with the wheelchair symbol. All rides have alternate entrances, and your GAC entitles you to them. At every park make sure you have a Guidebook for Guests with Disabilities. It has a listing with all of the WC entrances for every ride as well as a description of the ride and boarding requirements. It can be hard to find the regular WC entrance if you don't know where it is. You should never have to wait in the regular line for attractions unless you choose to.
The GAC also entitles you to cut line for the characters. We know that Wish kids do not have the stamina that other kids do, and that waiting in the hot sun is difficult for them. I was a performer on 2 CPs and every time we had a wish kid, we pulled them out of the line and brought them to the front. Apparently some people have been told the GKTW GACs don't work with characters- they are the only ones that work with the characters. As far as I know this has not changed.
I was also sad to see that one person said the CMs at Disney were not very accommodating and Universal was much better. Please know that this is the exception to the rule. When I was recruited for my first CP, one of the things they mentioned to us is that 3/4 MAW children choose WDW for their wish. They train everybody to anticipate the needs of MAW families, and most are more than happy to do so! For those of you who experienced less than friendly CMs, please accept my apologies. Most CMs love the MAW families and will do whatever they can to make it special!
Make sure you know about how tall he is so you can plan your rides since he may not make the height requirements. Some rides may als obe too intense for a 5 yo even if he makes the height requirement, so it's a good idea to get an idea in advance.
At that age, most kids love characters and have a special character they want to meet. A great place to do that is at a dining spot (although the characters are subject to change.) Communicate his favorite character to MAW and they will try to arrange some special time for you.
If he has a heart condition, I am assuming he has medication. Make sure that you have it with you at all times, and bring back up if you can! If there are any special dietary needs, communicate them to GKTW. Angels stock the villa with food and snacks before you arrive, and they will try to accommodate when necessary. The same is true for Disney Dining. They are amazing about making accommodations if you notify them in advance.
Have a general idea of what you want to do, and then be prepared to throw it all out of the window! Definitely take him to see Block Party Bash at Disney Hollywood Studios, it's our most interactive parade and the kids love it! Disney Dreams Come True in Magic Kingdom and Spectromagic are also amazing (although I might be biased, I used to perform in them.)
Be prepare to take naps in the Wish lounge or at your villa because it can be extremely tiring, especially for a child with a heart condition.
I'll post more as I think about it. I'm pretty knowledgeable about most of the rides and the parks, so if you have specific questions ,feel free to ask!