A: You need the Simple DirectMedia Layer (SDL) libraries, if you want to use one of the emulated VGA cards. Visit http://www.libsdl.org. To run the emulator you need the runtime libraries, to compile the emulator you need the development libraries. Make sure your compiler/linker can find the header and library files.
A: Compile without HAVE_SDL defined. For Windows, you can download the no_sdl version of the binary package. If you're on Windows, change the configuration file (gui=win32), if your system supports X-Windows (as is the case on most Linux/BSD/UNIX distributions, change it to gui=X11. If your system is not supported, remove the gui section alltogether, as well as any vga-card sections. Graphics support will not be available in this case.
A: You need the libpcap (Linux and others) or winpcap (Windows) packet capture libraries, if you want to use one of the emulated network cards. Visit http://www.tcpdump.org or http://www.winpcap.org. To run the emulator you need the runtime libraries, to compile the emulator you need the developer's pack. Make sure your compiler/linker can find the header and library files.
A: Your only option is to disable network support, by compiling without HAVE_PCAP defined. For Windows, you can download the no_net version of the binary package.
A: Support for big-endian host architectures has been available in the past, but since the primary developer of the ES40 Emulator no longer has a big endian machine, it has become difficult to support and maintain. If you can, please help us get the emulator working on big- endian architectures again!
A: Short answer: That depends on what the OS you intend to run on the emulator likes. Long answer: Right now, both cards are nearly identical (except for the PCI configuration ID, which tells the OS what card this is). In the future, the emulated Cirrus card may evolve into a more complete card, supporting various SVGA features. For the S3 Trio, this is more difficult, because documentation is harder to find. Since DECwindows on OpenVMS doesn't seem to like either of the cards, support for an entirely different card may be added in the future.