KS Signals ZS3 doesn't display "4".

Don't take the Signals from DTG. They are only shit.
Take the Signals from Schuster, the best working Signals for the Train Simulator.

Check this Category: http://rail-sim.de/forum/wsif/index.php/Category/63-Signale/

And here the Signals:

Deutsche KS-Signale V5.11 >>> http://rail-sim.de/forum/wsif/…eutsche-KS-Signale-V5-11/

Deutsche HV-Signale V6.1 >>> http://rail-sim.de/forum/wsif/…Deutsche-HV-Signale-V6-1/

Deutsche Formsignale V5.11 >>> http://rail-sim.de/forum/wsif/…utsche-Formsignale-V5-11/

Here some magnets & other Stuff:

Freeware Skript-Module und Signal-Trigger >>> http://rail-sim.de/forum/wsif/…odule-und-Signal-Trigger/

Skriptpaket HL-Signale >>> http://rail-sim.de/forum/wsif/…4-Skriptpaket-HL-Signale/

Skriptpaket HV-Signale >>> http://rail-sim.de/forum/wsif/…6-Skriptpaket-HV-Signale/

TSC - PZB Magnete inkl. GPA >>> http://rail-sim.de/forum/wsif/…TSC-PZB-Magnete-inkl-GPA/

Your welcome
And good luck with your Project