Having problems with the above. Two issues :
Specific calendars chosen seem to change randomly. Not often but it has happened a number of times.
I like showing empty days in my calendar. To achieve this I have an event that repeats daily with : as it's name. This shows in ios calendar, calendar 366 but not Goodtasks. Well it did until yesterday but again this had been irregular. This happens in the app store and beta version.
Thanks
Ian
Weirdly it isn't a problem on my iPad. I have different calendars in my iPad.
On my iPhone I have some subscription calendars that aren't on the iPad but none of these are used in Goodtask.
Ian
At the risk of thinking I should have waited, it appears the repeating event not appearing is linked to different calendars being on the two devices. When I go into General and ensure only the common calendars are checked then the smart lists seem to work.
I can see how this might be a problem for the app but I only subscribe to my daughters school calendar on my phone and it would be good if this didn’t cause an issue.
Ian
Hi Ian, thanks for the feedback.
Would you check 'Settings - Lists & Calendars - Calendars' and check how it's shown and what calendars are checked on both devices?
If you have different set of calendars, syncing lists may cause some changes during the sync process. You can turn off list sync inside 'Settings - iCloud Sync'.
Thanks!
I checked / ticked the same on both before my third post and the blanks started working.
Seems as if there still might be something funky going on as the subscribed calendars were ticked again.
If I turned off list sync then if I made other changes to the list on one device they would sync?
Ian
No, if you turn off 'Lists' in iCloud sync, things related to lists won't sync which are 'Lists, Excluded lists/calendars, list order, favorites'.
Thanks. That's what I thought. I need the lists to keep in sync.
Is there anyway to handle the calendar sync differently?
Ian
I'm not sure what you mean by handling differently.
Easiest way should be keeping calendars same for devices that needs sync. 
Keeping different calendars on different devices won't break the app but related settings can change during the sync process.
Thanks!
I've thought about it and one way you can take is using manual upload/download for syncing.
One downside would be you should edit/change list related on the device with more calendars (iPhone with shared calendars) and upload on that device and download on other when needed.
Thanks!