Thanks for your feedback hope that our experiences help
@Specialized Rider Care to find a solution. In the meantime, I do exactly what you say, the first time I lift up the back wheel until the walk engages, no errors on display show...at least this is the workaround I found, I would prefer to push and get the bike move immediately, I really don't get this intentional delay introduced in the last firmware...but have to live with it.
The walk mode takes about a complete crank turn (very slow) to engage a normal speed in walk mode, but if the chain is on the lowest gear (normal condition when I climb steep terrain), and there is some resistance (on steep terrain), and the magnet has just passed the speed sensor, the magnet probably will not reach the speed sensor again (the wheel will turn only 32/42 of the crank turns) before a speed sensor error detection.
I discovered that in Mission Control I have a message in Diagnostic, warning me for an error occurred to the speed sensor 3 days ago (when I tried the walk mode and saw the red bar and the blue just below flashing).
The message recommends to clean the speed sensor
Please Specialized tell me how can dirt impact the magnetic flux from the magnet on the brake disk and the sensor

The message also says to restart the bike in order to cancel the message error, but it remains.
I tried also with a reboot, but the error message remains.
The message ends "if you can't delete the error bring tke bike to a Specialized reseller"...
So, in summary, I had to pay in order to update 3 bikes for an update that corrects a Specialized issue, got a quite useless walk mode, got a fake error (clearly subsequent to the use of walk mode), and now I have to bring again the bike to a reseller and pay again for a Specialized mistake ?
Please, Specialized, test a bit better before relasing updates.
In this forum I'm not alone getting error message consequent walk mode, and how many people has used walk mode ?
I'm
sure you can reproduce it easily.
We're waiting for a soon update, user installable (at least for user already at 7.3.6), restoring a usable walk mode and allowing to delete the error message too (ok, I read the message and understand it, the error is stored in memory, now give me the choice to keep or cancel the message and store my answer in the log, if you like)