Glad to hear this worked eventually, because it gives me hope. I have spent hours trying to do this and haven't got it to work.
If you are saying it takes a long time, then I will persevere past the 7th press of the button.

Interesting that my Owners Manual has a slightly different set of instructions for the US vs Canada
For USA, it states that you need to press the Homelink button AND the garage door opener remote button simultaneously and keep it that way till the HomeLink flashes quickly.
For Canada, it states that you need to keep pressed the Homelink button and then keep pressing and releasing the opener remote button every 2 seconds or so until the Homelink flashes quickly. This is why my garage door keeps cycling every 2 seconds; but the Homelink button never learns!

 

so, for me, last night was when I picked up the NX. I spent 2-3 hours trying to program it to no avail. I cleared the codes, tried every combo of button pushing. Nothing, I called homelink and they state to do it the old way: press and hold the HL button and remote button simultaneously. Nope! That's the old HL.

Thr manual specifically states to press once and release. This is correct.

So this is what finally worked for me.

1) found a second controller. New battery and learned the remote to the opener.
2) unplugged the opener (anticipated on it not working and didn't want the door to keep opening)
3) cleared the HL by holding down 1 and 3 buttons.
4) presses the HL button I wanted to program once.
5) pressed and held the newly programmed remote (old Chamberlain clic remote)
6) surprisingly, it worked! LED changed color within a few seconds! Done!
7) pressed the HL button again. Not sure why I did but I did.

I didnt have to do the learn function on the opener like i like I was anticipating. My opener is dated 1/2000. Maybe I got lucky but I'm happy it's done.

if you are doing the learn step and are pressing it past three times, something is wrong and you need to start over.

 

Hi, I have a related question, guys. I cannot program more than one HomeLink button to open the garage door. Every time I program one of the remaining not programmed buttons, the first one I had programmed gets erased! So, at any time I can have only one button programmed for the same rolling code. The same happens with my other Lexus (2016 GS 350).
Is this your experience as well?

 

try moving the car out of range of the garage opener and that will help, sounds dumb and you may have to move your car down the street but it works