This problem happens in version 18-63c, and unfortunately, it seems that it will CONTINUE to happen... I found what is for me a HUGE bug, and what is for PCSOft a limitation NOT DESCRIBED anywhere in the help. So here goes...
The short version first: Parameters sent, in WebDev, to an awp page as INT on 8 can suddenly have incorrect values on the browser side...

Why is that a huge bug? In order to use the built in replication, you need to have your records automatic ID declared as INT on 8... Which means that you cannot currently use the built in replication with a webdev awp site if you need to pass a record ID as parameter (which is kind of a basis behavior) and maybe classic and php site too, but I haven't tested)...

How to test and see the beautiful effect:
- create an empty project, type awp
- create an empty page (awp also)
- in that page, add the 3 following lines:

1. In the global declaration of the page:

PROCEDURE PAGE_NoName2Loop(i8ID is int on 8=0)

2. In the Init of page (server)

info("Server init code: "+i8ID)

3. in the Load (browser) section

Info("Browser Load code: "+i8ID)

then test the page with the simple GO button, and enter as a parameter the following value:
187462334489315337 (please do not laugh, this is a REAL life value of an ID generated by HFCS 63c when an automatic replication has been set up)...

You will see the first info (in server code) displaying the correct value, and the second displaying instead 187462334489315330 (ie the same one, except for the last digit replaced by ZERO)
After some back and forth with PCSoft support, it appears that this is a JavaScript limitation, and therefore they cannot do anything about it.
One thing they should do is write it down in the help and also either block the entry of a too big value for the server ID in the replication system, or give you a strong message telling you that this replication system will have a problem if you use it with sme Javascript/browser code. Till then, you read about it here!
Please let me know if/when this problem is corrected/mitigated in any way.
WinDev, WebDev and WinDev Mobile consulting