Shahjada

please download archive page add-on again, looks like you are using old version of the add-on

it is something form your server, anyhow it also resolvable from plugin.
open download-manager.com
find and replace

base64_encode($id.'.hotlink')

with

rtrim(base64_encode($id.'.hotlink'),"=")

please download and install this add-on http://www.wpdownloadmanager.com/download/advanced-tinymce-button/

1) if you are not seeing some categories in archive page it is because of category access settings. keep access field empty to make it accessible for all and then it will be visible in archive page.

2) you need to replace the text directly from wpdm-archive-page.php

3) pagination css is in /download-manager/bootstrap/bootstrap.css

@ihero1970, try now

sorry, short-code is [wpdm-search-page]

within this month.

looks like your already resolved it.

will work for single domain only.
installation steps: http://www.wpdownloadmanager.com/docs/installing-wordpress-download-manager-pro/

ok, search will be implemented in that way with next update. Also wpdm pro coming with custom post type with next update

it will take little more time then regular page as that page loading 2000+ items, but as its now is regular, or you can also use other caching plugin.

thanks, it will be adjusted with next update.

1) no
2) yes, but that will only work for public downloads