[Xperia Z5 Compact Q&A, Help & Troubleshooting] creebefu:
I ended up leaving the phone alone for a while, and now it's powering off. I've gone through the process of installing flashtool, preparing the firmware. And now I have a new problem. When trying to flash this is what it says:

26/031/2015 08:31:50 - INFO - Please connect your device into flashmode.

26/031/2015 08:31:51 - INFO - Opening device for R/W

26/031/2015 08:31:51 - INFO - Start Flashing

26/031/2015 08:31:51 - INFO - Processing loader.sin

26/031/2015 08:31:51 - INFO - Checking header

26/031/2015 08:31:51 - ERROR - Processing of loader.sin finished with errors.

26/031/2015 08:31:51 - INFO - Ending flash session

26/031/2015 08:31:51 - ERROR -

26/031/2015 08:31:51 - ERROR - Error flashing. Aborted

26/031/2015 08:31:52 - INFO - Device connected in flash mode

I've followed instructions this to the best of my ability and not sure where I'm going wrong. I bought the phone unlocked in the UK so have selected United Kingdom - Customized UK (latest release 32.0.A.4.11 /R9B) in XperiFirm. Any help would be appreciated.

EDIT: I've got further than this now after clicking 'check drivers' in Flashtool but now I'm getting this error:

26/010/2015 09:10:14 - INFO - Device connected in flash mode

26/010/2015 09:10:24 - INFO - Selected Bundle for Sony Xperia Z5 Compact (E5823). FW release : 32.0.A.4.11_R9B. Customization : UK

26/010/2015 09:10:24 - INFO - Preparing files for flashing

26/010/2015 09:10:43 - INFO - Please connect your device into flashmode.

26/010/2015 09:10:44 - INFO - Opening device for R/W

26/010/2015 09:10:44 - INFO - Reading device information

26/010/2015 09:10:44 - INFO - Phone ready for flashmode operations.

26/010/2015 09:10:44 - INFO - Current device : E5823 - CB5A28S95H - 1298-5497_R9B - 1295-6639_32.0.A.4.11 - GENERIC_32.0.A.4.11

26/010/2015 09:10:44 - INFO - Start Flashing

26/010/2015 09:10:44 - INFO - Processing loader.sin

26/010/2015 09:10:44 - INFO - Checking header

26/010/2015 09:10:44 - INFO - Flashing data

26/010/2015 09:10:44 - INFO - Processing of loader.sin finished.

26/010/2015 09:10:45 - INFO - Loader : S1_Root_f936 - Version : MSM8994_50 / Boot version : S1_Boot_MSM8994_LA1.2_114 / Bootloader status : ROOTED

26/010/2015 09:10:45 - INFO - Processing partition-image.sin

26/010/2015 09:10:45 - INFO - Checking header

26/010/2015 09:10:45 - INFO - Flashing data

26/010/2015 09:10:45 - INFO - Processing of partition-image.sin finished.

26/010/2015 09:10:45 - INFO - Parsing boot delivery

26/010/2015 09:10:45 - INFO - Phone boot version : S1_Boot_MSM8994_LA1.2_114. Boot delivery version : S1_Boot_MSM8994_LA1.2_114

26/010/2015 09:10:45 - INFO - Boot delivery up to date. Nothing to do

26/010/2015 09:10:45 - INFO - Processing kernel.sin

26/010/2015 09:10:45 - INFO - Checking header

26/010/2015 09:10:45 - INFO - Flashing data

26/010/2015 09:10:49 - INFO - Processing of kernel.sin finished.

26/010/2015 09:10:49 - INFO - Processing fotakernel.sin

26/010/2015 09:10:49 - INFO - Checking header

26/010/2015 09:10:49 - INFO - Flashing data

26/010/2015 09:10:53 - INFO - Processing of fotakernel.sin finished.

26/010/2015 09:10:53 - INFO - Processing amss_fs_2.sin

26/010/2015 09:10:53 - INFO - Checking header

26/010/2015 09:10:53 - INFO - Flashing data

26/010/2015 09:10:53 - INFO - Processing of amss_fs_2.sin finished.

26/010/2015 09:10:53 - INFO - Processing modem.sin

26/010/2015 09:10:53 - INFO - Checking header

26/010/2015 09:10:53 - INFO - Flashing data

26/011/2015 09:11:01 - INFO - Processing of modem.sin finished.

26/011/2015 09:11:01 - INFO - Processing amss_fsg.sin

26/011/2015 09:11:01 - INFO - Checking header

26/011/2015 09:11:01 - INFO - Flashing data

26/011/2015 09:11:01 - INFO - Processing of amss_fsg.sin finished.

26/011/2015 09:11:01 - INFO - Processing amss_fs_1.sin

26/011/2015 09:11:01 - INFO - Checking header

26/011/2015 09:11:01 - INFO - Flashing data

26/011/2015 09:11:01 - INFO - Processing of amss_fs_1.sin finished.

26/011/2015 09:11:01 - INFO - Processing ramdump.sin

26/011/2015 09:11:01 - INFO - Checking header

26/011/2015 09:11:01 - INFO - Flashing data

26/011/2015 09:11:02 - INFO - Processing of ramdump.sin finished.

26/011/2015 09:11:02 - INFO - Processing ssd.sin

26/011/2015 09:11:02 - INFO - Checking header

26/011/2015 09:11:02 - INFO - Flashing data

26/011/2015 09:11:02 - INFO - Processing of ssd.sin finished.

26/011/2015 09:11:02 - INFO - Processing oem.sin

26/011/2015 09:11:02 - INFO - Checking header

26/011/2015 09:11:03 - INFO - Flashing data

26/011/2015 09:11:21 - INFO - Processing of oem.sin finished.

26/011/2015 09:11:21 - INFO - Processing persist.sin

26/011/2015 09:11:21 - INFO - Checking header

26/011/2015 09:11:21 - INFO - Flashing data

26/011/2015 09:11:22 - INFO - Processing of persist.sin finished.

26/011/2015 09:11:22 - INFO - Processing diag.sin

26/011/2015 09:11:22 - INFO - Checking header

26/011/2015 09:11:22 - INFO - Flashing data

26/011/2015 09:11:23 - INFO - Processing of diag.sin finished.

26/011/2015 09:11:23 - INFO - Ending flash session

26/011/2015 09:11:23 - ERROR -

26/011/2015 09:11:23 - ERROR - Error flashing. Aborted

26/011/2015 09:11:23 - INFO - Device connected in flash mode

26/011/2015 09:11:23 - INFO - Device disconnected

26/011/2015 09:11:30 - INFO - Device connected in flash mode

EDIT 2: I ran the program in 64 bit mode and let the program run and go through the xperifirm process by itself, and it went through fine.