Sorry for the confusion, but no - that snippet with the voltage data was from the logfile in post#6 above, I put in for comparison to what I was NOT seeing in my logfiles.
In my logfiles, I don’t see ANY data that would have been read from the PW - so perhaps it is an access issue, but I can get the data using the same URLs in a webbrowser on the same machine.
FWIW, this is on a fresh installation of Windows 8.1.
powerwall.ini:
#
# The Powerwall gateway API url
#
# Replace 127.0.0.1 with the gateway IP address
#
url=http://192.168.0.63/api/meters/aggregates
#
# Poll the URL every n seconds
#
poll=30
# Define the power direction
#
# 'in' - Consumption (load)
# 'out' - Solar Generation (solar)
direction=in
# uncomment to read an alternative power value
#
# default is 'instant_power'
#
# power=instant_power
# uncomment to read voltage data
#
voltage=instant_average_voltage
# uncomment to upload state of charge percentage to extended parameter
#
soc-url=http://192.168.0.63/api/system_status/soe
soc-parameter=v11
# extended data v7-v12
#
# valid values [site|battery|load|solar|busway|frequency].[instant_power|instant_reactive_power|instant_apparent_power|frequency|energy_exported|energy_imported|instant_average_voltage|instant_total_current|i_a_current|i_b_current|i_c_current]
#
# e.g. battery.instant_power
#
# uncomment to upload data to v7
#
v7=battery.instant_power
# uncomment to upload data to v8
#
v8=load.instant_power
# uncomment to upload data to v10
#
v10=site.instant_power
# uncomment to upload data to v11
#
# v11=load.frequency
# uncomment to upload data to v12
#
v12=solar.instant_power
output of http://192.168.0.63:80/api/meters/aggregates
> {"site":{"last_communication_time":"2018-05-26T20:34:19.187556399+10:00","instant_power":3.4200000762939453,"instant_reactive_power":24.469999238848686,"instant_apparent_power":24.707838093833825,"frequency":49.95000076293945,"energy_exported":22020.84000015187,"energy_imported":79682.14000015186,"instant_average_voltage":728.0899963378906,"instant_total_current":0,"i_a_current":0,"i_b_current":0,"i_c_current":0},"battery":{"last_communication_time":"2018-05-26T20:34:19.190209041+10:00","instant_power":970,"instant_reactive_power":-10,"instant_apparent_power":970.0515450222221,"frequency":49.963,"energy_exported":92140,"energy_imported":104380,"instant_average_voltage":238.8,"instant_total_current":-22.900000000000002,"i_a_current":0,"i_b_current":0,"i_c_current":0},"load":{"last_communication_time":"2018-05-26T20:34:19.187385067+10:00","instant_power":979.0476892891847,"instant_reactive_power":-25.523438422695016,"instant_apparent_power":979.3803264367776,"frequency":49.95000076293945,"energy_exported":0,"energy_imported":210092.96472222224,"instant_average_voltage":728.0899963378906,"instant_total_current":1.3446794959600437,"i_a_current":0,"i_b_current":0,"i_c_current":0},"solar":{"last_communication_time":"2018-05-26T20:34:19.187385067+10:00","instant_power":-0.47999998927116394,"instant_reactive_power":2.200000047683716,"instant_apparent_power":2.2517549155067185,"frequency":49.95000076293945,"energy_exported":164833.10833333628,"energy_imported":161.44361111405405,"instant_average_voltage":238.3300018310547,"instant_total_current":0,"i_a_current":0,"i_b_current":0,"i_c_current":0},"busway":{"last_communication_time":"0001-01-01T00:00:00Z","instant_power":0,"instant_reactive_power":0,"instant_apparent_power":0,"frequency":0,"energy_exported":0,"energy_imported":0,"instant_average_voltage":0,"instant_total_current":0,"i_a_current":0,"i_b_current":0,"i_c_current":0},"frequency":{"last_communication_time":"0001-01-01T00:00:00Z","instant_power":0,"instant_reactive_power":0,"instant_apparent_power":0,"frequency":0,"energy_exported":0,"energy_imported":0,"instant_average_voltage":0,"instant_total_current":0,"i_a_current":0,"i_b_current":0,"i_c_current":0},"generator":{"last_communication_time":"0001-01-01T00:00:00Z","instant_power":0,"instant_reactive_power":0,"instant_apparent_power":0,"frequency":0,"energy_exported":0,"energy_imported":0,"instant_average_voltage":0,"instant_total_current":0,"i_a_current":0,"i_b_current":0,"i_c_current":0}}