I have two problems with the Citation (QUAY tag) Confidence (CERTAINTY_ASSESSMENT / QUALITY_OF_DATA). In FTB Windows 188.8.131.526 if you select a Citation Certainty of "Unreliable evidence or estimated data" then this setting is lost and reverts to 'not specified'.
If you select a certainty of 'Questionable...', 'Secondary...' or 'Direct...' then all appears ok.
Until you look at the GEDCOM 5.5 export output. The standard gives the following values for the CERTAINTY_ASSESSMENT - the value that follows the QUAY tag.
0 = Unreliable evidence or estimated data
1 = Questionable reliability of evidence (interviews, census, oral genealogies, or potential for bias for example, an autobiography)
2 = Secondary evidence, data officially recorded sometime after event
3 = Direct and primary evidence used, or by dominance of the evidence
But I'm getting values of 4 for 'Direct...', 3 for 'Secondary...' and 2 for 'Questionable...' being output in the GEDCOM file. I have no examples of 'QUAY 0' or 'QUAY 1' because they are being lost as detailed above.