It appears that this program is unable to communicate with an R5C and has difficulties with a Rebel XS.
Canon lists several cameras that do not permit full remote control
EOS M100 EOS M6 EOS M5 EOS M10 EOS M3 EOS M2 EOS M
Many newer Canon cameras have mechanical shutters whose maximum speed is 1/4000. CE will require an f/stop of 7.1 for this to be acceptable. This means these cameras may not be compatible with CE if they are paired with a fast telescope (anything less than 7.1) or a lens that is restricted. Some of the "R" series cameras have an electronic as well as a manual shutter which may remove that limitation by manually configuring "electronic shutter only" and running with the mount mode set to "monopod/ship" {this is not fully confirmed as of this writing}.
PowerShot V10 (Firmware version 1.1.0 or later) EOS R100 PowerShot ZOOM (Firmware version 1.2.0 or later) EOS R50 EOS R8 EOS R6 Mark II EOS R10 EOS R7 EOS R3 EOS Kiss M2 / EOS M50 Mark II EOS R5 EOS R6 EOS Kiss X10i / EOS Rebel T8i / EOS 850D EOS Ra EOS-1D X Mark III EOS M200 EOS M6 Mark II EOS 90D PowerShot G7X Mark III PowerShot G5X Mark II EOS Kiss X10 / EOS Rebel SL3 / EOS 250D / EOS 200D II EOS RP PowerShot SX70 HS EOS R EOS Kiss M / EOS M50 EOS Kiss X90 / EOS REBEL T7 / EOS 2000D / EOS 1500D EOS REBEL T100/EOS 4000D / EOS 3000D EOS 6D Mark II EOS Kiss X9 / EOS Rebel SL2 / EOS 200D EOS Kiss X9i / EOS Rebel T7i / EOS 800D EOS 9000D / EOS 77D EOS 5D Mark IV EOS-1D X Mark II EOS 80D EOS Kiss X80 / EOS Rebel T6 / EOS 1300D EOS 5DS EOS 5DS R EOS 8000D / EOS REBEL T6sEOS 760D EOS Kiss X8i / EOS REBEL T6i / EOS 750D EOS 7D Mark II EOS Kiss X70/EOS 1200D/EOS REBEL T5/EOS Hi EOS 70D EOS Kiss X7 / EOS 100D / EOS REBEL SL1 EOS Kiss X7i / EOS 700D / EOS REBEL T5i EOS-1D C EOS 6D EOS Kiss X6i / EOS 650D / EOS REBEL T4i EOS-1D X EOS 5D Mark III EOS Kiss X50 / EOS REBEL T3 / EOS 1100D EOS Kiss X5 / EOS REBEL T3i / EOS 600D EOS 60D EOS Kiss X4 / EOS REBEL T2i / EOS 550D EOS-1D Mark IV EOS 7D EOS Kiss X3 / EOS REBEL T1i / EOS 500D EOS 5D Mark II EOS 50D EOS DIGITAL REBEL XS / 1000D/ KISS F EOS DIGITAL REBEL Xsi / 450D / Kiss X2 EOS-1Ds Mark III EOS 40D EOS-1D Mark II