Hi @spike, welcome in the forum 
for your information, there is an unofficial build on Pie made for the i9100. I don’t know if it could be useful.
To solve the error 7 issue, use TWRP 3.3.1 instead of the 4.0.0.
Hi @spike, welcome in the forum 
for your information, there is an unofficial build on Pie made for the i9100. I don’t know if it could be useful.
To solve the error 7 issue, use TWRP 3.3.1 instead of the 4.0.0.