@Renate... Hello again!
I think I figured out - finally - how to install the new loader. It appears to work, if I read the following correctly...
Mark@MacBook-Air ~ % adb reboot edl
Mark@MacBook-Air ~ % edl --loader=/Users/Mark/Desktop/0014d0e100000000_d40eee56f3194665_FHPRG.bin
Capstone library is missing (optional).
Keystone library is missing (optional).
Qualcomm Sahara / Firehose Client V3.53 (c) B.Kerler 2018-2021.
main - Using loader /Users/Mark/Desktop/0014d0e100000000_d40eee56f3194665_FHPRG.bin ...
main - Waiting for the device
main - Device detected

main - Mode detected: sahara
Device is in EDL mode .. continuing.
sahara -
------------------------
HWID: 0x0014d0e100000000 (MSM_ID:0x0014d0e1,OEM_ID:0x0000,MODEL_ID:0x0000)
Unknown CPU, please send log as issue to
https://github.com/bkerler/edl
PK_HASH: 0xd40eee56f3194665574109a39267724ae7944134cd53cb76 7e293d3c40497955
Serial: 0xc3253440
sahara - Uploading loader /Users/Mark/Desktop/0014d0e100000000_d40eee56f3194665_FHPRG.bin ...
Successfully uploaded programmer

firehose - INFO: Chip serial num: 3273995328 (0xc3253440)
firehose_client
firehose_client - [LIB]: No --memory option set, we assume "eMMC" as default ..., if it fails, try using "--memory" with "UFS","NAND" or "spinor" instead !
firehose
firehose - [LIB]: Couldn't detect MaxPayloadSizeFromTargetinBytes
firehose
firehose - [LIB]: Couldn't detect TargetName
firehose - TargetName=Unknown
firehose - MemoryName=eMMC
firehose - Version=1
firehose_client - Supported functions:
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