You're right, I can now get 95 countries with "t=lc&q=all" but the ITEMS structure is different with "all", it has less fields :
without all:
"COUNT": "16",
"ITEMS": [
[
"23",
"au",
"Australia ",
"30",
"243",
"38",
"4199",
"1264",
"2935",
"AUD",
"8.99",
"11.99",
"14.99"
],
with all:
"COUNT": "95",
"ITEMS": [
{
"id": "276",
"country": "Angola ",
"lastUpdated": "2017-09-19 04:47:10"
},
{
"id": "21",
"country": "Argentina ",
"lastUpdated": "2017-09-19 10:01:22"
The iso code and some other values are not present in the "all" call :-(