Need to convert it to “time” after you compiled it as string:
maxima of (it as time) of (substring (8,2) of it as day_of_month & substring (5,2) of it as integer as month & first 4 of it as year & substring (11,8) of it as local zoned time_of_day) of (preceding text of first " [" of lines containing “*E: SpApi::updateEnginesConfig: Operation failed” of it) of file “D:\install-virgo-win64.log”
And since you are doing the comparison by “time”, you should go back to using “now”:
(it < (now - 1*hour)) of maxima of (it as time) of (substring (8,2) of it as day_of_month & substring (5,2) of it as integer as month & first 4 of it as year & substring (11,8) of it as local zoned time_of_day) of (preceding text of first " [" of lines containing “*E: SpApi::updateEnginesConfig: Operation failed” of it) of file “D:\install-virgo-win64.log”