Everything seems to be working fine now.
Thank you Eli and Robert for your hardwork.

Here is "Welcome to Emacs" in Sanskrit in the Brahmi script rendered correctly in Emacs!
𑀈𑀫𑁃𑀓𑁆𑀲𑁂 𑀲𑁆𑀯𑀸𑀕𑀢𑀫𑁆 (ईमैक्से स्वागतम् īmaiksē svāgatam)

On Sun, Apr 17, 2022 at 7:31 PM Robert Pluim <rpluim@gmail.com> wrote:
>>>>> On Sun, 17 Apr 2022 18:19:47 +0530, समीर सिंह Sameer Singh <lumarzeli30@gmail.com> said:

    समीर> Vowel signs U+1103E U+1103F U+11040 and U+11041 are not connected properly
    समीर> to conjuncts.

    समीर> Here are the codepoints of the text I entered:
    समीर> 11013 11046 11032 1103E (𑀓𑁆𑀲𑀾)
    समीर> 11013 11046 11032 1103F (𑀓𑁆𑀲𑀿)
    समीर> 11013 11046 11032 11040 (𑀓𑁆𑀲𑁀)
    समीर> 11013 11046 11032 11041 (𑀓𑁆𑀲𑁁)

How about this?

diff --git a/lisp/language/indian.el b/lisp/language/indian.el
index 0a50dd999f..ef095ddc3b 100644
--- a/lisp/language/indian.el
+++ b/lisp/language/indian.el
@@ -397,7 +397,7 @@ malayalam-composable-pattern
 ;; Brahmi composition rules
 (let ((consonant     "[\U00011013-\U00011034]")
       (non-consonant "[^\U00011013-\U00011034\U00011046\U0001107F]")
-      (vowel         "[\U00011038-\U0001103D\U00011042-\U00011045]")
+      (vowel         "[\U00011038-\U00011045]")
       (numeral       "[\U00011052-\U00011065]")
       (multiplier    "[\U00011064\U00011065]")
       (virama        "\U00011046")

Robert
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