Hi there...
I see you have an active thread over on props and it looks like you're getting some good help over there.
I'll chime in about your routine and techniques. One thing I see is that you're doing PU/PD but LO is only 5 months, right? We usually don't start using PU/PD until 6 months since it's too stimulating before that. I would stick to shh/pat and HTTJ, sounds like you're having some success lately with those for extending naps?
As for your routine, if she only naps for 1.5h, you really need to shorten the next A time a bunch. I'd do under 2h myself. I think she's way OT and that's why you're getting the EW now since it's all just building on itself. This might mean she ends up with too many naps in a day, but more sleep is better (even if it's broken up) until we can get her naps to lengthen. Some of the nap lengthening is developmental, too, so it should come with time. It's hard for me to post a goal routine since I think your goal looks good but you just need to tweak a bunch every day according to how she naps each time.
You may end up with a super early BT if you shorten up A's during the day, too, but that's ok. Don't be afraid to put her in bed at 6pm. Sounds nuts, but it will really help with the OT.
If she has a cold now you may have to just ride it out for a few more days. It's impossible to teach independent sleep to a sick baby.
But she'll be better soon and you'll get going again.
I think you're really on the right track. Sounds like from your other post that things are getting better and that you know where you're headed. I think shying away from PU/PD for now and doing some routine tweaking will help a bunch.
What do you think?