The problem of the Nexus 5 is caused by a change in the radio/baseband software. It looks like Qualcomm switches off rSAP in new radio versions for whatever reason. Maybe the phone manufacturer has to pay an extra fee for rSAP support? I don't know... I took a look at the baseband software if there is a chance to re-enable the rSAP functions, but I must confess that I don't understand anything that's happening inside.
So far it only helps to flash the 4.2.2 radio software under 4.4.4. See this thread for more info.
The problem so far affects the Moto G, the OnePlus One and probably the Oppo Find 5 & 7. Even worse, a second phone seems to run into problems after a firmware update: the Sony Xperia Z2. Maybe it's also possible to flash the previous radio software separately.
There is one good news: The HTC One m8 seems to receive official rSAP support with the latest firmware update! Let's hope this is not by accident and HTC will also support rSAP in future phones!
Recently Google rolled out Android 4.3, which brought with it a big challenge for root access: It is no longer possible for Android apps to call a setuid process. SuperSU has a workaround for that restriction, so you need a recent version for Android 4.3 to continue using root apps. rSAP is affected because I also used a small setuid app which no longer works on 4.3. rSAP version 2.3.3 contains a fix to let the app run with Android 4.3 on the Nexusses.
While all American and European phone makers completely ignore the SIM access profile, it seems to be more popular in Asia. First of all of course Samsung as the largest phone maker further supports it in their phones, recently in the Galaxy S4 Mini. Now more and more Chinese phone makers seem to equip their phones with rSAP. Some phones with Mediatek chipset support rSAP, although I don't know how well it works. Now I found out that the Xiaomi MI2S also supports rSAP out of the box.
It's time for the Americans and Europeans to copy from the Chinese
This is very strange... The only drivers that worked for me on a 32 bit Windows 7 are these:
Set Phone to USB Diag Mode
You need to install all drivers
setprop sys.usb.config diag