The AppImage as provided on the CINELERRA-GG website has all of the capabilities and features of a standard original "single user" build based on the cinelerra-5.1/bld.sh script with additions to suit the operating system level on which the binary is built. For example, currently the CinGG-yyyymmdd-x86_64.AppImage is created from the binary built to include the opencv plugins and the library libsvtav1 (SVT-AV1 encoder). Whereas the 32-bit older AppImage, CinGG-yyyymmdd-i386.AppImage, does not have those extras added when its binary is built so that the resulting AppImage does not include those specific features. In addition, the website AppImage includes the graphics hardware/software capabilities of the computer where the binary is built. This means that specific graphics hardware/software capabilities that exactly match your computer's will not be included in the AppImage unless your computer graphics exactly matches the computer where it was created; in terms of capabilites this refers to graphics software such as vaapi/vdpau/onevpl, etc.
Since it is possible that a .deb, .rpm, or any release available from the internet is built in a method that differs from the standard or recommended way, such as enabling or disabling libraries, then their capabilities/features could be different than the CINELERRA-GG website AppImage.
Briefly stated, the AppImage has the exact same FFmpeg version, codecs, encoders, windows, formats, tools, navigation methodologies, editing functions, effects, shortcuts, etc. and everything works the exact same way as the binary from which it is derived.
There is one different capability that is notable, although not necessary if you only use the X11 video driver instead of the optional X11-OpenGL driver. The OpenGL libraries, for example libGLU.so, are not included in the AppImage but are expected to already be installed on the user's computer. So if using an AppImage with the OpenGL video driver, you will need to install the appropriate OpenGL drivers for your Operating System graphics board. This should not be an issue because usually OpenGL is already installed. In practice to date, no problems have been reported with the OpenGL main libraries/drivers compatibility between the AppImage build computer and the user computer.
AppImage uses a mix of statically-added thirdparty libraries embedded in the "cin" binary and the system's dynamic libraries put into a self-extracting squashfs archive. This means that the system's dynamic libraries in the AppImage are picked up from the build computer. By contrast, an rpm package depends on those dynamic libraries from the system to be present and compatible between the build system and the system that the rpm is installed on.
In the case of FFmpeg, AppImage as well as any standard built package, uses the thirdparty version included with the CINELERRA-GG source code because there are currently a set of 13 required patches specific to this usage. This is due to the fact that these patches would not be present in the system's installed FFmpeg version so that some esoteric things might not work correctly, like creating a bluray disc. With the AppImage or a package build, the CINELERRA-GG FFmpeg binary is never installed in the user's system. You do not have access in the AppImage to the actual FFmpeg binary but in a build system the FFmpeg binary would be found in your build subdirectory of cinelerra-5.1/thirdparty/ffmpeg-version. FFmpeg is built for CinGG without all possible options included as they are not needed and this is standard for the way it is built as a package or for an AppImage. A team of quasi-developers and quasi-moderators work to keep FFmpeg version updated with the released version, ensure the patches work as designed, and add minor changes.
AppImages on the website are usually updated at the end of the month in order to ensure that the latest changes, fixes, and library updates are available to the user. The user can continue to use their current version, but it is recommended to update the AppImage at their convenience - at least every six months.
Because the AppImage does not give you direct access to any of the specific CINELERRA-GG files, customization involving those files is not possible directly. Here is a list of the specific customization you can not do with an AppImage. However, by unpacking the AppImage and getting its structure into folders and files you still can do almost all customizations as documented in various sections of this manual. See the section Managing AppImage on how to do this.