diff --git a/.flowconfig b/.flowconfig
index e5a7c21..9f2a25d 100644
--- a/.flowconfig
+++ b/.flowconfig
@@ -36,6 +36,3 @@ module.file_ext=.js
 module.file_ext=.njs
 module.ignore_non_literal_requires=true
 suppress_comment= \\(.\\|\n\\)*\\$FlowIgnore
-
-[lints]
-deprecated-declare-exports=off
diff --git a/bits/05_buf.js b/bits/05_buf.js
index ac12910..bf3bcbf 100644
--- a/bits/05_buf.js
+++ b/bits/05_buf.js
@@ -7,12 +7,12 @@ function new_raw_buf(len/*:number*/) {
 	/* jshint +W056 */
 }
 
-function s2a(s/*:string*/) {
+function s2a(s/*:string*/)/*:any*/ {
 	if(has_buf) return new Buffer(s, "binary");
-	return s.split("").map(function(x){ return x.charCodeAt(0) & 0xff; });
+	return s.split("").map(function(x/*:string*/)/*:number*/{ return x.charCodeAt(0) & 0xff; });
 }
 
-function s2ab(s/*:string*/) {
+function s2ab(s/*:string*/)/*:any*/ {
 	if(typeof ArrayBuffer === 'undefined') return s2a(s);
 	var buf = new ArrayBuffer(s.length), view = new Uint8Array(buf);
 	for (var i=0; i!=s.length; ++i) view[i] = s.charCodeAt(i) & 0xFF;
diff --git a/bits/35_custprops.js b/bits/35_custprops.js
index ebaa3ae..2bfb5db 100644
--- a/bits/35_custprops.js
+++ b/bits/35_custprops.js
@@ -57,7 +57,6 @@ function write_cust_props(cp/*::, opts*/)/*:string*/ {
 	if(!cp) return o.join("");
 	var pid = 1;
 	keys(cp).forEach(function custprop(k) { ++pid;
-		// $FlowIgnore
 		o[o.length] = (writextag('property', write_vt(cp[k]), {
 			'fmtid': '{D5CDD505-2E9C-101B-9397-08002B2CF9AE}',
 			'pid': pid,
diff --git a/bits/48_stybin.js b/bits/48_stybin.js
index dc593e9..ed6baff 100644
--- a/bits/48_stybin.js
+++ b/bits/48_stybin.js
@@ -58,7 +58,7 @@ function parse_BrtFont(data, length/*:number*/, opts) {
 
 	return out;
 }
-function write_BrtFont(font, o) {
+function write_BrtFont(font/*:any*/, o) {
 	if(!o) o = new_buf(25+4*32);
 	o.write_shift(2, font.sz * 20);
 	write_FontFlags(font, o);
diff --git a/misc/flow.js b/misc/flow.js
index 57fc498..76ae4b3 100644
--- a/misc/flow.js
+++ b/misc/flow.js
@@ -29,6 +29,7 @@ type WBWBProps = {
 	Names?: Array<any>;
 	Views?: Array<any>;
 	WBProps?: WBProps;
+	SheetNames?: Array<string>;
 };
 
 type WBProps = {
@@ -61,6 +62,8 @@ type WBWSProp = {
 interface CellAddress {
 	r:number;
 	c:number;
+	cRel?:boolean;
+	rRel?:boolean;
 };
 type CellAddrSpec = CellAddress | string;
 
@@ -122,6 +125,8 @@ type ColInfo = {
 	wch?:number;     // width in characters
 
 	MDW?:number;     // Excel's "Max Digit Width" unit, always integral
+
+	customWidth?:boolean;
 };
 
 interface Margins {
diff --git a/misc/flowdeps.js b/misc/flowdeps.js
index 2099b41..e8d7675 100644
--- a/misc/flowdeps.js
+++ b/misc/flowdeps.js
@@ -1,14 +1,14 @@
 /*::
 declare module 'exit-on-epipe' {};
 
-declare module 'xlsx' { declare var exports:XLSXModule; };
-declare module '../' { declare var exports:XLSXModule; };
+declare module 'xlsx' { declare module.exports:XLSXModule; };
+declare module '../' { declare module.exports:XLSXModule; };
 
-declare module 'commander' { declare var exports:any; };
-declare module './jszip.js' { declare var exports:any; };
-declare module './dist/cpexcel.js' { declare var exports:any; };
-declare module 'crypto' { declare var exports:any; };
-declare module 'fs' { declare var exports:any; };
+declare module 'commander' { declare module.exports:any; };
+declare module './jszip.js' { declare module.exports:any; };
+declare module './dist/cpexcel.js' { declare module.exports:any; };
+declare module 'crypto' { declare module.exports:any; };
+declare module 'fs' { declare module.exports:any; };
 
 type ZIP = any;
 
diff --git a/xlsx.flow.js b/xlsx.flow.js
index 7fd5ee5..f95cee8 100644
--- a/xlsx.flow.js
+++ b/xlsx.flow.js
@@ -132,12 +132,12 @@ function new_raw_buf(len/*:number*/) {
 	/* jshint +W056 */
 }
 
-function s2a(s/*:string*/) {
+function s2a(s/*:string*/)/*:any*/ {
 	if(has_buf) return new Buffer(s, "binary");
-	return s.split("").map(function(x){ return x.charCodeAt(0) & 0xff; });
+	return s.split("").map(function(x/*:string*/)/*:number*/{ return x.charCodeAt(0) & 0xff; });
 }
 
-function s2ab(s/*:string*/) {
+function s2ab(s/*:string*/)/*:any*/ {
 	if(typeof ArrayBuffer === 'undefined') return s2a(s);
 	var buf = new ArrayBuffer(s.length), view = new Uint8Array(buf);
 	for (var i=0; i!=s.length; ++i) view[i] = s.charCodeAt(i) & 0xFF;
@@ -4194,7 +4194,6 @@ function write_cust_props(cp/*::, opts*/)/*:string*/ {
 	if(!cp) return o.join("");
 	var pid = 1;
 	keys(cp).forEach(function custprop(k) { ++pid;
-		// $FlowIgnore
 		o[o.length] = (writextag('property', write_vt(cp[k]), {
 			'fmtid': '{D5CDD505-2E9C-101B-9397-08002B2CF9AE}',
 			'pid': pid,
@@ -8247,7 +8246,7 @@ function parse_BrtFont(data, length/*:number*/, opts) {
 
 	return out;
 }
-function write_BrtFont(font, o) {
+function write_BrtFont(font/*:any*/, o) {
 	if(!o) o = new_buf(25+4*32);
 	o.write_shift(2, font.sz * 20);
 	write_FontFlags(font, o);
diff --git a/xlsx.js b/xlsx.js
index 2e713f7..c0a05d9 100644
--- a/xlsx.js
+++ b/xlsx.js
@@ -4105,7 +4105,6 @@ function write_cust_props(cp) {
 	if(!cp) return o.join("");
 	var pid = 1;
 	keys(cp).forEach(function custprop(k) { ++pid;
-		// $FlowIgnore
 		o[o.length] = (writextag('property', write_vt(cp[k]), {
 			'fmtid': '{D5CDD505-2E9C-101B-9397-08002B2CF9AE}',
 			'pid': pid,