try S:FS for the S:1/15 bit ...
there really is no S:4 equivalent ... most people create a "free running timer" using its own Done bit as an XIO to automatically reset the timer ... then use a suitable bit from the ACCumulator much as you once used the S:4 bits ...
for example: My_S4_Timer.ACC.10 might be useful as a "flashing bit" ...
for most of the other "status type" stuff that you'll be looking for later, read up on the GSV instruction ...
the secret handshake is that you have to use a GSV to Get System Values from the processor's brain - and then store those values into suitable memory locations ("tags") that you yourself create ... once that's done, the data will have valid "addresses" and the information can then be used in your program ...