That is something else unrelated to the IR driver bug that has just been fixed. I've just tested my xbox 360 white media remote (looks exactly like the one in the screenshot in my osmc) and it is working perfectly on the latest update.
A few things to check:
1) Make sure you are actually running the right kernel. From ssh:
osmc@vero3-db:~$ cat /proc/version
Linux version 3.14.29-21-osmc (root@vero4k) (gcc version 4.9.2 (Debian/Linaro 4.9.2-10) ) #1 SMP Sun Jun 11 20:02:40 UTC 2017
Check that you have version 3.14.29-21-osmc and that date and time matches as well.
2) Try using the irw command to see if keypresses from the remote are being delayed or whether the problem lies in Kodi. From ssh run irw then press some buttons on the remote:
67 0 KEY_UP linux-input-layer
67 1 KEY_UP linux-input-layer
67 0 KEY_UP_UP linux-input-layer
6a 0 KEY_RIGHT linux-input-layer
6a 1 KEY_RIGHT linux-input-layer
6a 0 KEY_RIGHT_UP linux-input-layer
6c 0 KEY_DOWN linux-input-layer
6c 1 KEY_DOWN linux-input-layer
6c 0 KEY_DOWN_UP linux-input-layer
69 0 KEY_LEFT linux-input-layer
You should see an event immediately when you press a button and it should keep repeating if you hold the button down. If you see this immediately but Kodi doesn't respond until a lot later the problem is elsewhere with Kodi.
If the output from irw is delayed as well or seems very intermittent, my first guess would be some sort of light interference on the IR sensor such as from daylight or a faulty energy saving bulb - fluorescent energy saving bulbs have been known to cause flicker that can upset IR receivers, and I have had this problem before on different devices.
Try to shroud any light sources from the vero4k and test the remote again with a good line of sight, if that works then it is probably a lighting issue in the room - try turning off specific lights to find which one it is.
Another thing you could try is to plug in and use the external IR receiver dongle if you are not using it, or remove it if you are.
Finally, check the room for any other IR remotes that may have an object on top of them holding a button down - if another remote in the room is broadcasting an IR code even if it is partially obscured it can interfere with other remotes in the room. Yes I've had this happen too, as spare remotes sit in a box that often gets toys dumped on top of them by a 1 year old...