I have found a message on a website which says that Spectrogram application has been discontinued which means no updates will be available any more. Based on this, I can confirm that the main cause to your issue is related to compatibility. While you may have the possibility of installing it on a new operating system, its functionality will be questionable due to modules and files not being compatible with the operating system.
One way to use the application again is through virtualization using VirtualBox or VmWare. VirtualBox allows you to install all sorts of operating systems (Windows included).
Note: You need an original installation disc or ISO for the OS you want to install to run Spectrogram.