I find using dynamic folders, and tags very usefull. I save tagged pics in folders which are an unpublished parent folder, subfolders using the same names as I my personal archives (and that is very usefull to easylly update a specific file).
Albums are generated using dynamic folders and tags. This is also usefull to avoid storing many of the same pics, because it is used in several albums. But ... I can't find a way to control pics orders.

Using Sort subalbums by: "manual" and Sort images by "manual" change the order, but do not use the order used in the unpublished folder (I do not understand how it work).
Is there a way to control pics order in dynamic folders ?

You cannot order images in dynamic albums manually as in real albums, only via the "sort images by" settings of the album. That's because they are saved searched and change whenever more images meet the condition. They cannot use setting of the real albums because images can be from numerous albums and this is not "stored" but "queried".

This is also usefull to avoid storing many of the same pics, because it is used in several albums.

Yes, but also be careful and constantly check your SEO indexing. Normally the images point canonically to the real album they belong to so you don't get "duplicate content" issues (> html_meta_tags plugin needed)

Thanks for the answer. Is a workaround existing ?
Choosing sorting by manual (vs *gallery image sort order) in dynamic folders totally change the order, how does it work ?
Then the order is constant, but unpredictable.

Choosing the dynamic folder thumbnail work very well.

Another question, is it possible to change the search parameters (tags) used by a dyncamic folder, after it was created ?
The only way I have found is to delete it, and recreate it.

For sorting there is no workaround. The best is to use a general order by ID, date, title etc the images within a dynamic album. Same for albums within a dynamic album. Manual probably is mixing up manual order which is of course unique to each fo the source albums if the images are from more than one album.

Again, dynamic albums are technically searches.

Another question, is it possible to change the search parameters (tags) used by a dyncamic folder, after it was created ?
Yes. Dynamic albums are stored in your albums folder as .alb files which can be opened and edited with every text editor.

Yes. Dynamic albums are stored in your albums folder as .alb files which can be opened and edited with every text editor.

Indeed, sorry, totally forgot to reply to that. And before you ask: It's on the (long) list to have a interface for that in the future.

It is simple like that, thanks.