"Download client for ..." on Status page (v 2.5.31 running on QNAP QTS

Hi

I have 2 installs on QNAP NAS, once adding a client, i have 2 boxes to allow me to download the client, on the second install, these boxes dont show up… how do i get them to show? (see image, underlined in red)

UPDATE
The install with NO Client Install buttons, when i try and add a client, and click download for the Windows install i get “ERROR: Signature verification failed”, so is the install broken? There both install from the identical server software, granted the QNAP OS is different though. If i copy the server signature and manually add it to the client it works ok, so the server does have a signature.