1. Why do I see differences in GA report and Daton output? 
   Ans: There could be a few reasons for this -

(i) GA reports may be sampled. Make sure that the report you generated has Green Tick instead of an Orange one as shown below - 
 

(ii) If you are validating data for recent days make sure _daton_golden flag is set to TRUE in the records for these days. If the flag is FALSE then it's sampled data and Daton is yet to fetch un-sampled data for those days.

(iii) Use the same set of dimensions in both Daton and GA custom reports for comparison

2. GA Tables are empty in Daton 
   Ans: Create a custom report in GA and verify whether the dimensions and metrics you selected has data at all. It's advised to create a custom report first and then create integration on Daton only if the custom report is valid.
3. Will Daton support Enhanced Ecommerce metrics and dimensions? 
   Ans: Yes. Go through Google Analytics documentation for descriptions of metrics and dimensions and select the required combination in Daton.
4. Will Daton support Custom Dimensions?  
   Ans: Yes. Users must know which custom dimension has been mapped in GA and use them in Daton.
5. Getting "Invalid combination of dimensions and metrics" error notification 
   Ans: The combination of metrics and dimensions is invalid and one has to go to edit integration workflow and remove invalid items. It's advised to create a custom report first and then create integration on Daton only if the custom report is valid. Additionally, validation of combinations would be added in Daton UI  before creating the integration in upcoming release.
6. Getting "Invalid Grant" error notification  
   Ans: The token for the user account had been invalidated by Google Analytics. Go to edit integration workflow and renew the token by authenticating again. Read more about Refresh Token Expiration.