Your description of stock shifter behaviour sounds very unusual.
Unless of course you have some monster power in your grip
In every instance, especially when cold, all 1series cars I drove required considerable amount of effort to go past first and engage into reverse.
There is no way you could do it in error... perhaps if your shifter was much taller than stock it would be possible, otherwise, noway.
It has always been second>first for me, on all cars I owned.
Saves first gear synchros and once it becomes a habit, it's hard to do it any other way.
My stock knob was pretty hard to pop-off. Not impossible, but hard.
New ZHP knob was a different story - it had to be slammed into place with brute force, otherwise it would not fully click in place and kept coming off at first.
Also, it needs clearance space to fully engage, so if there's anything under it (like the boot fold etc) it will not lock in place.