diff --git a/doc/4-instrument/README.md b/doc/4-instrument/README.md
index 2bfcd4091..d8fa8b2ee 100644
--- a/doc/4-instrument/README.md
+++ b/doc/4-instrument/README.md
@@ -50,8 +50,9 @@ The very first numeric entry sets the visible width of the bars in sequence-type
 Each macro has two buttons on the left.
 - Macro type (explained below).
 - Timing editor, which pops up a small dialog:
-  - Step Length (ticks): Determines how many ticks pass before each change of value.
-  - Delay: Delays the start of the macro until this many ticks have passed.
+  - Step Length (ticks): Determines how many ticks pass before each change of value. Default is 1.
+  - Delay: Delays the start of the macro until this many ticks have passed. Default is 0.
+  - The button is highlighted if either of these is set differently from default.
 
 ## macro types
 
diff --git a/doc/4-instrument/macro-ADSR.png b/doc/4-instrument/macro-ADSR.png
index d01e177ef..8d12c7c63 100644
Binary files a/doc/4-instrument/macro-ADSR.png and b/doc/4-instrument/macro-ADSR.png differ
diff --git a/doc/7-systems/tia.md b/doc/7-systems/tia.md
index 8b89616d4..9e6d9cfa6 100644
--- a/doc/7-systems/tia.md
+++ b/doc/7-systems/tia.md
@@ -184,7 +184,7 @@ this chip uses the [TIA](../4-instrument/tia.md) instrument editor.
 |    30 |    32.7 |  C-1 |  0.0 |    32.5 |  C-1 |  -11
 |    31 |    31.7 |  B-0 |  +44 |    31.5 |  B-0 |  +33
 
-## shapes 8
+## shape 8
 
 | pitch |    NTSC | note | cent |    PAL  | note | cent
 |------:|--------:|:----:|-----:|--------:|:----:|-----: