Here is a possible fix for the heptic feedback not working on the lockscreen slider....
I dont know if the issue is affecing everyone or just some people, but I have read some comments by some of the heptic on the lockscreen not working
Im not currently running SS 5.4 so please bear with me on the specific location of things, not sure if Ill be exact but ull get the jist of it.
I know its in Settings for sure, duh, then I believe-CyanogenMod settings-Input-Heptic feedback tweaks- first make sure heptic feedback main is checked, if so then go to "set down pattern" now the default order (going from top down) according to my defaults is: 0, 1, 20, 21
Now at the top right click the "-" 3 times removing all but one of the sequences which should be "ms On Time", now set that # to 40, click save (make sure to click save) let it save, go back to your main screen & you MUST REBOOT your phone for the settings/changes to be applied..
Only downside is this will increase the heptic feedback on your softkeys, but in exchange your heptic feedback on your lockscreen slider will work.
And I suggested to set it at "40" for testing, if it works for ya, you can always decrease the # later.
Let me know if it works.