You can download an SMS app from the Play Store, like Handcent or GoSMS to customize your SMS appearance.
As for like flow, try going to the app drawer, long press the icon, drag it to "App Info", then press "Clear Data" and reboot your phone.
Sent from my Nexus 4
Thanks. I'll check those out.
The app doesn't show in the app drawer. Went to Settings > App > Light Flow > Clear Data. Restarting now. Still the same, opens to a black screen.
I've checked the Light Flow box in Accessibility (it also said to check an Accessibility box, but I have no idea where that box is).
If you're using the stock launcher, that's weird that it doesn't show in the app drawer. I'd try uninstalling and reinstalling it.
Sent from my Nexus 4
No idea then. If it were me, I'd get root access working, backup my apps with Titanium Backup, do a factory reset, install only Light Flow from the Play Store and see if that works. If it works, then restore the other apps using Titanium.
Sent from my Nexus 4