diff --git a/src/mame/amiga/agnus_copper.cpp b/src/mame/amiga/agnus_copper.cpp
index 688ebf6c5c5..a4c74d4e802 100644
--- a/src/mame/amiga/agnus_copper.cpp
+++ b/src/mame/amiga/agnus_copper.cpp
@@ -312,13 +312,14 @@ int agnus_copper_device::execute_next(int xpos, int ypos, bool is_blitter_busy,
 		if (word0 >= m_cdang_setting)
 		{
 			// SKIP applies to valid MOVEs only
-			// - apocalyps (gameplay)
+			// - apocalyps (gameplay, chain of SKIPs & WAIT)
+			// - rbisland (loading screen at least, tries to SKIP a CDANG MOVE)
 			if (m_state_skipping)
 			{
 				LOGINST("  (Ignored)\n");
 				m_state_skipping = false;
 				// TODO: verify timings
-                // may depend on num of planes enabled (move_offset) or opcode fetch above is enough.
+				// may depend on num of planes enabled (move_offset) or opcode fetch above is enough.
 				xpos += COPPER_CYCLES_TO_PIXELS(2);
 				return xpos;
 			}
diff --git a/src/mame/amiga/amiga_m.cpp b/src/mame/amiga/amiga_m.cpp
index d529e683e7e..e0e2118c7ae 100644
--- a/src/mame/amiga/amiga_m.cpp
+++ b/src/mame/amiga/amiga_m.cpp
@@ -1365,8 +1365,10 @@ uint16_t amiga_state::custom_chip_r(offs_t offset)
 
 		case REG_CLXDAT:
 			temp = CUSTOM_REG(REG_CLXDAT);
-			CUSTOM_REG(REG_CLXDAT) = 0;
-			return temp;
+			if (!machine().side_effects_disabled())
+				CUSTOM_REG(REG_CLXDAT) = 0;
+			// - "Barney [& Freddy] Mouse" requires bit 15 high all the time
+			return temp | (1 << 15);
 
 		case REG_DENISEID:
 			return CUSTOM_REG(REG_DENISEID);