So recent cake can actually be address from tc filters, so onr option would be to still use sqm-scripts with layer_cake and set up two filters to place torrents into the bulk tin and game traffic into the high pririty tin. Not as nifty as your example, but if all that is required is to sort stuff into three priority classes that should be fine 
But how to do this?
first run "tc -s qdisc" and figure out the major number of the cake instance in question:
qdisc cake 801b: dev pppoe-wan root refcnt 2 bandwidth 9545Kbit diffserv3 dual-srchost nat split-gso rtt 100.0ms noatm overhead 34 mpu 64
In this example 801b for interfave pppoe-wan, and remember that number
Then look at the tins for diffserv3:
verage network hdr offset: 0
Bulk Best Effort Voice
thresh 596560bit 9545Kbit 2386Kbit
target 30.5ms 5.0ms 7.6ms
interval 125.5ms 100.0ms 102.6ms
1 being Bulk or Background and remember this as minor number.
Then all you need to do is to add a filter for the torrent port:
tc filter add dev pppoe-wan parent 801b: protocol ip u32 match ip dport 60435 0xffff action skbedit priority 801b:1
Mind you I have not tested that myself, but this was reported to work on the cake mailing list. @ldir can you spot an error of my copy of your command above