The Subfolders cannot be used normally

I try www.yourDomain.com/site1  just from nosourcepackage and used the newly generated database, and setup the iis and cloudflare  General settings .. The website is operational ,but
1.  Nivo Slider not working :
The subdirectory path "a1" under the subdomain appears twice Subfolders...
https://testnop.xxx/a1/a1/Plugins/Widgets.NivoSlider/Scripts/jquery.nivo.slider.js?v=FXfc2kFdkHLx66RZk-KQknKwaLY

2. And Can not into The Administation
(error 500)


ps:
my store table ref


There's something else I haven't noticed, and I'd like to ask you all to help me find the reason.
Thank you.

Add the relative path of the application I set in IIS

You cannot have the nopCommerce application inside another application subdirectory
The nopCommerce application must be in the root directory

Thanks for your reply,
Because the customer's primary domain name cannot be changed,
I wonder if there are other methods, such as whether I can use iis urlwerite?

How to  explain why it can only be placed as root?
But there is a mention about Wildcard copyright removal key in the link www.yourDomain.com/site3... It seems that it can be work at subfolder? https://www.nopcommerce.com/en/nopcommerce-copyright-removal-key
tks!!

You can host the NopC application as a subdomain if that works for you. So instead of www.yourDomain.com/site1 you can host the app separately in the IIS server and create the binding with www.site1.yourDomain.com

Please!
If subfolder is really not supported, I would like to know the real reason, or was it supported in previous versions?
After all, I need the customer to indicate whether to reapply for a new certificate, but this is a trouble for the customer.

You could do it when system used asp.net
Now it is a function that is not supported by .NetCore
It is not something blocked by nopCommece

Thanks for the clear answer, this could save us or someone a lot of testing time.