Looks like you found a bug! It appears to me from the log and your variable name that Optimize is attempting to sort the column names for your raw data table, which includes columns for each variable. When column (/variable) names include numbers as well as letters, we try to extract these numbers and then sort according to those, so that eg
Variable1 is sorted to come before
Variable2. Unfortunately, we assumed that the digits within column names would be Integer, and if your variable names include numbers like
52352345634654756756867534 these are too large to be parsed to Integer.
I have opened a bug ticket for this: OPT-5063
If you would like to be notified of when we resolve the issue I think you have to open a support case, then we can link the issue to the support case and you will get an automatic email notification when the issue is resolved.
In the meantime to circumvent the issue you could consider renaming your variables to not include large numbers. Apologies for the inconvenience!