We encountered this issue trying to save into an Excel file from an extraction. Exactly due to the same reasons, we started to use the EXTRXXXX file automatically saved by the extraction, instead of saving into Excel. You need to choose "File" as "Destination" instead of "List", and the extraction saves the file as EXTRXXXX in RAMP in the Impftp.lnk//Extract folder, where XXXX is the extraction number. I believe the file is in CVV format, which can easily be saved to the local machine afterwards.
I did not inquire with RAMP at that time, but this problem predates Citrix in our case. It can still be due to a 2X/Citrix protocol issue, but I suspect that the length of the file and virus protection on our end may be causing a timeout issue.
We never tried to save files into Excel directly after moving to Citrix. I would be curious to know, what RAMP has to say, if you decide to contact them.
We have already contacted the RAMP migration team. We are waiting for responses.